WriteHuman Review (2026): The Real Monthly Price, Capacity Caps & Detector Limits

What WriteHuman is (and who it's for)

WriteHuman is an AI text humanizer at writehuman.ai, launched in 2023. It rewrites machine-written copy so AI detectors are more likely to score the result as human-written, nudging two statistical signals toward human territory: perplexity, a measure of how predictable each next word is, and burstiness, how much sentence length and rhythm vary across a passage. Paid plans return several rewrite variations per request. WriteHuman also bundles its own AI detector for text and images, ships a Chrome extension, and since mid-2026 runs an MCP server that lets an AI assistant call it directly.

It is built for two readers: the marketing content writer shipping posts on a schedule, and the freelancer sizing a monthly plan against client word volume before quoting a rate.

One name collision to clear first, because it sends people to the wrong product. A Chrome extension called "WriteHuman - History Replay for Google Docs", published by a different developer at nextgrowthlabs.com and carrying roughly 9,000 users, replays the edit history of a Google Doc, which is how teachers check the way a draft was written. That is the opposite job, and several school-related threads under this name are about it. Everything below refers to writehuman.ai.

How we reviewed this

This review rests on WriteHuman's documented features, its pricing read directly from writehuman.ai/pricing on September 4, 2026 and on August 19 before that, three archived captures of the same page, and 13 of the 15 dated user reports we gathered, each linked individually below. That is a paper trail, not a lab session, and nothing here is presented as a test we ran.

There is a correction to make first, and it is ours. From June 7 to August 19, 2026 this page published $12, $18 and $36 as WriteHuman's flat monthly prices. Those are the annual-billed rates. Paying month to month cost $18, $27 and $48 on the ladder as it stood then, which was half again as much on Basic and Pro and a third more on Ultra. The page also carried no capacity data at all, so nobody could work out which plan they needed, and it put the free tier's cap at 200 words when the real figure is 250. Wayback captures of the vendor's pricing page from March 25, 2026, June 8, 2026 and August 18, 2026 all show the same ladder, the earliest two and a half months before we published. This was not a vendor price change we failed to catch. It was wrong from the day it went live.

There is a second note, dated today, and it is a different kind of thing. Reading the vendor's pricing page again on September 4, 2026 shows five of the six paid figures higher than they were on August 19. Month to month, Basic is $20, Pro is $29 and Ultra is $59. On annual billing Pro is $19 a month and Ultra is $39, charged as $228 and $468 for the year. Basic's annual rate of $12 a month, charged as $144, is the only paid figure that did not move. This one is not a misreading of ours. The vendor raised its prices somewhere between our two reads, which it is entitled to do, and we had not caught it until today. Sixteen days separate those reads, which is the practical reason this page now carries the date its prices were last checked rather than a promise about how often we look.

Disclosure, because it is load-bearing here: we earn a commission if you subscribe through our link, which is exactly why an error in the vendor's favour cannot sit on this page uncorrected. Our review policy covers how this works. Last updated September 4, 2026, the date the prices above were read.

Pricing: monthly vs. annual, and what each plan actually gets you

WriteHuman has four plans and two billing cadences, and the gap between them is the whole story. The pricing page loads with the yearly toggle already selected and prints the discounted per-month figure in large type, with the annual total smaller inside the same card. That display is why, when we surveyed the competing pages ranking for this tool in August 2026, three of them quoted three different Pro prices ($18, $22 and $24), none labelled with a billing cadence, and why ours was wrong too. None of those three matches Pro's September price on either cadence.

Those are the September 4, 2026 figures, taken from the plan cards and checked against the vendor's own compare table. Five of the six paid numbers are higher than the ones this table carried on August 19, which is a vendor price rise and a separate matter from the reading error described above.

Read the right-hand column before you commit. Annual billing here is one payment up front, not $39 arriving monthly, so Ultra on annual billing means $468 leaves your account on signup day. The vendor prints its own saving figure beside each paid plan: "Save $96/yr" on Basic, "Save $120/yr" on Pro and "Save $240/yr" on Ultra. Those are the vendor's numbers rather than ours, and each one reconciles exactly with twelve months of month-to-month billing minus the annual charge. The size of that gap is not even across the ladder: month to month costs two-thirds more than annual on Basic, and about half again more on Pro and on Ultra.

Two terms are worth settling before that payment leaves. Cancelling is self-serve, documented in WriteHuman's own help centre article on how to cancel a subscription, which answers a question one user asked in a thread cited below and never got answered. Refunds are the harder edge, and WriteHuman's own terms of service, read directly at writehuman.ai/terms on August 27, 2026, settle it plainly in Section 11, "Purchases and Payment": "All purchases are non-refundable." Cancellation is the only lever on offer, and it "will take effect at the end of the current paid term" — so cancelling mid-cycle stops the next charge without returning any of the one you already paid. That supersedes the 14-day window our previous version cited tentatively from WriteHybrid (June 27, 2026), a review published by a competing humanizer that we had not been able to confirm against WriteHuman's own pages; the vendor's own terms carry no such window, so treat WriteHybrid's figure as superseded rather than as a right you can rely on. Practically, that leaves the free tier and the smallest plan you can stomach as the only real way to test WriteHuman, since a disappointing month on Ultra has no refund path back out. Get that in writing from support before you accept it secondhand from this page or any other.

This annual-preselected display is not unique to WriteHuman. It is one of the patterns our own Pricing Transparency Audit coded across the AI pricing pages it sampled, and WriteHuman's page is one of the coded records. The study measures how often the headline number on an AI pricing page is a per-month-billed-annually figure; it does not name this vendor in its text, and this page is a textbook instance.

The capacity ladder this page never carried

Price alone cannot tell you which plan you need, because WriteHuman meters two things at once: how many humanizer requests you get a month, and how many words fit in each request. Multiply them and you have the number that decides the purchase. Every quota below was re-read on September 4, 2026 and none of them changed when the prices did.

Two of those columns appear on no competing review we checked. Output variations are how many different rewrites come back from one request, so Pro's three attempts at a paragraph cost the same single request as Basic's two. Detection checks and image scans belong to the bundled detector, metered separately from the humanizer.

One friction point the vendor's page does not mention and three separate Reddit reports do: unused requests do not carry into the next month.

Cost per 1,000 words

Multiplying requests by the per-request word cap gives each plan a monthly word ceiling, and dividing the price by that ceiling gives the number nobody in this category publishes. The four rows below are our own arithmetic on the vendor's published prices and caps, not figures the vendor prints anywhere.

Pro costs roughly 58% more than Basic on annual billing, $19 against $12, and buys five times the capacity, so its per-word cost is better by more than three times. That inverts the intuition the pricing page encourages. On this ladder the entry tier is the expensive one per word. The September rise barely touched that comparison: Pro's annual rate per 1,000 words moved from $0.075 to $0.079, while Basic's held at $0.25 because Basic's annual price did not change.

Ultra has no fixed ceiling, so its per-word cost falls the harder you push it. At 90,000 words a month, which is 30 requests filled to the 3,000-word cap, annual Ultra is $0.43 per 1,000 words and month-to-month is $0.66. At 240,000 words, where Pro tops out, it is $0.16 and $0.25. Annual Ultra only undercuts a fully used Pro past roughly 490,000 words a month. Below that, Ultra buys you the 3,000-word single-request ceiling, not a better rate.

One caveat on all four rows: they assume you use every request and fill each to its cap. Send 80 requests of 400 words on Basic and you have used 32,000 words, which is $0.375 per 1,000 on annual billing, half again the $0.25 the full-use row above implies. Partial requests are the quiet way this ladder gets more expensive than it looks.

The free tier: a sampler, not a plan

WriteHuman free gives you 3 requests a month at 250 words each, with 1 output variation, plus 10 detection checks and 10 image scans. That is 750 humanizer words a month. An 800-word post does not fit in one request, so testing a real article means splitting it across the entire monthly allowance and stitching the pieces back together, which changes the result you are trying to evaluate. Our earlier version said 200 words per request, a figure still circulating elsewhere: EssayDone's WriteHuman review, bylined April 7, 2025, prints it, and so does webseotrends.com's, whose own page markup records a last update of 2026-04-04. The vendor's page has said 250 since at least March 2026.

The bundled AI detector, on every tier including Free

WriteHuman ships its own AI detector alongside the humanizer, and the pricing page states plainly that every plan includes full access to both. That sentence appeared verbatim on the page we read on August 19, 2026 and in the June and August captures, and the arrangement it describes is unchanged in the September 4, 2026 read. Our previous version never mentioned it, which was a real omission, because a checker you would otherwise pay for separately is part of what the subscription buys.

What "full access" does not mean is unmetered. The detector carries two quotas of its own, separate from humanizer requests: text detection checks and image scans, the second for judging whether an image was AI-generated. Free gets 10 of each a month, Basic 160 checks and 80 scans, Pro 400 and 200, and Ultra unlimited on both. The September price rise left every one of those quotas exactly where they were, so on every paid tier except Basic's annual rate you now pay more for the same detector allowance.

The structural caveat matters more than the quota. A vendor's own detector scoring that vendor's own humanizer output is a closed loop, and a clean result there tells you nothing about the checker your client, editor or institution runs. Use it as a fast first pass, then verify against the detector that decides, whether that is GPTZero, Originality.ai or an internal one.

MCP access, explained for non-developers

MCP stands for Model Context Protocol, an open standard for letting an AI assistant connect to an outside service and call its functions. In plain terms: instead of opening writehuman.ai, pasting a draft, copying the rewrite and pasting it back, your assistant does that step itself, inside whatever you already work in.

WriteHuman runs an MCP server for exactly this. Its documentation lists three functions an assistant can call: humanize_text, which returns scored rewrite variations, detect_ai_text, which returns an AI-probability score with a human, AI or mixed classification, and a free account check for your remaining quota. Authentication is OAuth-based, so you connect your account instead of passing an API key around, and connecting it is a single terminal command (claude mcp add writehuman --transport http https://writehuman.ai/api/mcp/v1). If you do not work inside one of those assistants, this is a feature to ignore, not a reason to upgrade.

Access is gated to Pro and Ultra, and Ultra's is capped at 1,000 calls a month. Here the vendor contradicts itself on one page: all three paid pricing cards list "MCP access" as a bullet, Basic included, while the compare table directly below states Basic gets none, Pro gets it, and Ultra gets 1,000 a month. We treat the compare table as accurate because it is the more specific, but if MCP is why you are buying, check what your account shows early. The Pro call cap is published nowhere we could find, and we will not guess one.

Neither rival this page compares against records an equivalent. Our own reviews document an API on all four paid tiers at Undetectable AI and no self-serve API at all at Phrasly, and an MCP server on neither. No competing WriteHuman review we read mentions the feature.

When the free tier and Basic stop being enough

The free plan breaks at a predictable point: 750 words a month, one variation, and a 250-word ceiling no real article fits under. It answers one question, which is whether WriteHuman's output clears your detector on a single paragraph of your own writing.

Basic breaks at a less obvious point, and this is where the capacity table earns its place. Its 600-word cap means a 1,000-word article takes two requests, so 80 requests a month really cover 40 finished pieces, and the effective cost rises from $0.25 to $0.30 per 1,000 words on annual billing, or from $0.417 to $0.50 month to month. Splitting a piece also means the tool never sees the whole document at once, the condition under which the Originality.ai result below gets worse. Pro's 1,200-word cap absorbs a standard blog post in one request, drops the real cost to $0.095 per 1,000 words annually, and adds a third variation to choose from.

The counter-case: publish fewer than twenty pieces a month, none past 600 words, and Basic is enough while Pro is wasted money. That case got slightly stronger in September, because Basic's annual rate was the one paid figure the vendor left alone while Pro's went up. If Originality.ai checks your work at length, no tier on this ladder fixes that, because it is a property of the output and not the plan.

Does WriteHuman actually work? Multi-detector pass rates

WriteHuman's results split sharply by detector, and the spread is wider than any single headline number suggests. The documented pass rates in the table above are aggregated from public reporting and segmented by content length where the sources allowed it, not measured by us. They are also the same six figures our June 2026 version published, carried forward unchanged and not re-tested on this pass or the August one.

They also need a currency caveat this page did not previously carry. The vendor's banner in the June 8, 2026 capture announces an enhanced model "updated for GPTZero 4.6b and Originality", dated June 1, six days before we first published these figures. The August 18, 2026 capture names a further update, referencing GPTZero and Pangram. The percentages describe a model version already superseded when we published it, and superseded again since: a dated snapshot, not a live measurement.

One distinction competing reviews blur: ZeroGPT and GPTZero are different products from different companies. A humanizer that clears one tells you nothing about the other, and the documented gap is large, around 82% against roughly 48%.

If you want per-detector, per-content-type granularity beyond a single number per detector, webseotrends.com publishes a disclosed 53-run matrix across five detectors and four content types. It is deeper than anything we can honestly offer while we run no tests of our own, and pointing at it costs us nothing worth keeping.

The Originality.ai word-count collapse past 400 words

This is still the single most useful finding on the page. WriteHuman's documented Originality.ai pass rate is low to begin with, around 19% on short documents, and past roughly 400 words it collapses toward 0%. The mechanism is structural: a short passage gives a detector little to weigh, while the same humanized style stretched across a full article accumulates repeated patterns until the detector has more than enough signal. The tool wins on small samples and loses on large ones. No plan upgrade changes this.

Turnitin

The documented Turnitin AI pass rate sits near 28%, too low to be dependable for any submission where the verdict carries weight, and Turnitin's AI module is a separate system from its similarity check, which no humanizer affects. Two dated user reports describe the same outcome from the user's side, both cited in the next section. We report this as a factual ceiling on what the product does, not as advice for routing around academic-integrity systems.

Why cleaning up the grammar afterwards can undo the work

One competing review published a test worth citing precisely because it cuts against the vendor's pitch. EssayDone, dated April 7, 2025, ran a 176-word sample through WriteHuman, then accepted Grammarly's suggested corrections on the humanized text and re-ran the detectors. The scores moved sharply in the wrong direction: Originality.ai from 2% to 100%, GPTZero from 1% to 82%, Quillbot from 0% to 70%, ZeroGPT from 25% to 50%. Two caveats belong with it: one sample, run once, and EssayDone sells a competing humanizer without disclosing that conflict in the review. The takeaway survives both. Finish your grammar and readability edits first, humanize last, and leave the output alone.

What real users report

Fifteen dated user reports were gathered for this refresh, all from Reddit, and thirteen are cited below. Sentiment splits seven negative, four mixed and four positive, with the negatives clustering in posts that describe extended real use and the positives in passing "which tool should I try" mentions. No account names appear here because the archive recorded comment permalinks without usernames, and guessing one would be worse than omitting it.

Output quality is the dominant theme, in five of the fifteen. A month-long user in r/AIToolTesting (December 10, 2024) reported output that kept an artificial feel and needed manual editing afterwards. A marketer in r/AskMarketing (November 24, 2024) reached the same conclusion while praising the built-in detector. A poster in r/studytips (March 25, 2025) ran the output through an independent quality check and reported 4 out of 10, saying it clears detectors sometimes but the quality is low. Three replies in that thread agreed: one preferred a competitor for quality (March 26, 2025), one went with a different tool after being unimpressed (March 25, 2025), and one gave the sharpest explanation in this whole research pass (March 25, 2025): detectors do not flag weak vocabulary or clumsy grammar as machine-written, so a rewrite can score better while reading worse.

Detection reliability is the second theme, with a precision note attached. Three reports describe inconsistent results against stricter detectors, Turnitin in particular, but two of the three phrase it as something many users report instead of a first-person incident, so this is one witnessed account plus two secondhand summaries, not three independent failures.

Billing friction is the third, in three reports. The r/AIToolTesting and r/AskMarketing reviewers both state that unused credits do not roll over, the second comparing it to paying for a full meal and getting a snack, and both describe support as slow or absent. A commenter under that second post (December 21, 2024) asked outright how to cancel a WriteHuman subscription and got no answer in the thread. The vendor's own help centre documents that flow, linked in the pricing section above.

The positive reports are real but thin, and they share a shape: WriteHuman turns up as a known name in a list of options, not as a first choice. It appears among worthwhile low-cost humanizers (April 24, 2025) and among viable alternatives to another tool (March 20, 2025), and, most usefully, as "decent" by someone who had tried several and called two rivals unreliable (November 2, 2024). One comparative mention (January 5, 2025) put a competitor ahead for nuanced writing. Fifteen reports from one platform is a small sample: read this as the shape of the complaints, not a failure rate. One note on their currency: every report here predates both the August correction and the September price rise, so the low-cost framing in the positive mentions was written against a cheaper ladder than the one on sale today.

One last report dates our own error. A commenter in r/ChristUniversity (October 27, 2024) put the free tier at 200 words per attempt, the figure this page carried until August and several competing reviews still carry. The vendor's page has said 250 since at least March 2026, so that number kept travelling long after it stopped being true.

Vendor claim vs. reality

WriteHuman markets itself as a humanizer that clears AI detectors, with a pricing-page footer promising to elevate AI to human perfection. The user record does not support reading that as a guarantee: an independent quality check scored the output 4 out of 10, a month-long user reported Turnitin still flagging the text, and a separate marketer's review described the same pattern. The documented pass rates above say it more precisely, which is that the answer depends on which detector you face.

The second contradiction is the vendor's with itself, on one page. Each of the three paid pricing cards lists MCP access as an included bullet, Basic among them. The compare table immediately below states Basic gets none. Both were live on the page we read on September 4, 2026 and on August 19, and both appear in the June and August captures.

A promotional posting pattern worth knowing about

Anyone researching this tool on Reddit should know what the results contain. Of the 100 most recent comments matching this product's name in the public Reddit archive, 69 belong to two referral-tagged promotional waves. The first is 28 near-identical short recommendations from 28 different accounts across unrelated subreddits inside a two-day window on June 9 and 11, 2024, each carrying the same referral tag. The second is roughly 40 near-identical copy-pasted comments from a single account across roughly 40 unrelated subreddits between April 8 and 27, 2025, carrying a different tag. One user called out the second pattern (May 6, 2025), noticing that every recommended link in a supposedly independent "I tested 16 humanizers" post carried the same commission tag.

We describe only what is observable: the wording, the account counts, the timeframe and the tags. We are not in a position to say who wrote or paid for any of it, and none of those 69 comments is counted in the fifteen reports above. WriteHuman runs a public affiliate program, as do most tools in this category, and so, disclosed at the top of this page, do we.

What's changed

1. March 25, 2026, the earliest archived capture. The ladder that would hold until at least mid-August 2026 is already in place: Free at 3 requests of 250 words, Basic at $12 annual or $18 monthly, Pro at $18 or $27, Ultra at $36 or $48. The word "MCP" appears nowhere in that capture.
2. June 1, 2026. A banner announces an enhanced model updated for GPTZero 4.6b and Originality, six days before our original review published its detector figures.
3. Between March and June 2026, MCP launches. The June 8 capture promotes WriteHuman MCP for agents as new, the likeliest reason our original review never mentioned it.
4. By August 18, 2026. A further model update, naming GPTZero and Pangram. The same capture adds a Chrome Web Store listing, four API landing pages and a Claude watermark-remover line. Every price and capacity figure is unchanged.
5. August 19, 2026. We restated the three paid prices on both cadences, corrected the free tier from 200 to 250 words, added the capacity ladder and the per-1,000-word costs, and documented the bundled detector and MCP access for the first time.
6. September 4, 2026, this update. A fresh read of the vendor's pricing page, checked against its own compare table, finds five of the six paid figures higher than in the August 18 capture: month-to-month Basic $18 to $20, Pro $27 to $29 and Ultra $48 to $59; annual Pro $18 to $19 a month and annual Ultra $36 to $39. Basic's $12 annual rate and $144 annual charge are unchanged, as is every quota and feature on the ladder. The vendor now prints a saving figure against each paid plan: $96, $120 and $240 a year. Prices, per-1,000-word costs and the comparison table below are recomputed here. The detector pass rates are the same dated snapshot as before and were not re-tested.

Alternatives to WriteHuman

Only the WriteHuman column was read from the vendor on September 4, 2026. The Undetectable AI and Phrasly figures are carried over from our reviews of those two tools and were not re-checked on this pass, so treat them as of those reviews' own dates.

WriteHuman vs Undetectable AI

Undetectable AI is the closest comparison on shape and the cheaper one to start with. It meters a flat monthly word pool instead of requests: 10,000 words costs $9.99 a month or $5.00 on annual billing, rising through $19, $31 and $42.50 a month for 20,000, 35,000 and 50,000 words, with API access on all four paid tiers and a one-time 250-word trial. The per-word picture flips at volume: its entry tier is $1.00 per 1,000 words month to month against WriteHuman Basic's $0.417, and its best published rate of about $0.43 annually is well behind WriteHuman Pro's $0.079. WriteHuman wins on capacity per dollar. Undetectable AI wins on the smallest payment you can make, on eight rewrite modes, on 30-plus languages, and on an API at every paid level where WriteHuman gates MCP to Pro and above.

WriteHuman vs Phrasly

Phrasly sells one unlimited-style plan at about $19.99 a month billed month-to-month, with a roughly 5,000-word ceiling per run and no request meter. Its annual rate is unsettled: our sources split between about $10.99 and about $12.99 a month, and with its pricing page refusing our checks we could not establish which is current. Two things decide this comparison. Phrasly's entry path carries more risk: the free allowance is a one-time sample disputed between 300 and 550 words, and the $2 3-Day Access pass is non-refundable and auto-renews into the full subscription unless you cancel inside three days. WriteHuman's free tier is smaller, but it renews monthly and expires quietly instead of converting. Against that, Phrasly's per-run ceiling is larger than any single WriteHuman request including Ultra's 3,000 words, and our Phrasly review publishes no pass-rate figures at all, where WriteHuman's weakness at length is at least documented.

Two more worth a look: HumanizeMy AI is built around academic and ESL writing, and Humbot bundles more tools, though its pricing page publishes no figures to a logged-out visitor, so it cannot be compared on price. BypassGPT comes up constantly in these searches and we have not reviewed it, so we will not rank it here. The wider field is in our guide to the best AI humanizers.

Is WriteHuman legit?

Yes, in the sense that matters. WriteHuman is a real, established product launched in 2023, drawing roughly 3.7M monthly visits as of late 2024, with a working bundled detector, a Chrome extension and, since mid-2026, an MCP server. It is not a fly-by-night site.

On sentiment, we are retiring a claim instead of repeating it. This page previously said Trustpilot sentiment skews positive, citing no specific review and no date. We have not opened Trustpilot on either of the last two passes, so the only figure we can date is the one Google's own result card displayed for WriteHuman's Trustpilot page in mid-August 2026: 3.8 stars from about 291 reviews. That is a search-result display, not a reading of Trustpilot, so treat it as a pointer and go look for yourself.

One thing to weigh while you read around. Two of the most visible WriteHuman reviews in search results are published by rival humanizers: one written by Undetectable AI's own founder, and the EssayDone review cited earlier, which closes by recommending its own tool. Neither states the conflict on the page. We sell no humanizer and no detector, and the commission disclosed at the top is the only stake we have.

Reliability is the separate question: strong documented results on lighter detectors, a documented collapse against Originality.ai at length, output that five of fifteen dated reports say needed editing afterwards, requests that expire monthly, and a pricing page whose cards disagree with its own comparison table. Set alongside the promotional posting pattern above, the reasonable position is to trust the product and verify the claims, ours included.

Verdict

WriteHuman holds its 3.3 out of 5, and the score stayed put for a reason worth stating. Nothing the product does has changed since August. What changed is the set of numbers this page prints, and it changed twice: we corrected our own misreading on August 19, then the vendor raised five of its six paid figures before we read the page again on September 4. Month to month now costs two-thirds more than annual on Basic and about half again more on Pro and Ultra, and annual billing still takes the whole year at once. Against that sit two features this page had never documented before August, a detector bundled on every plan including the free one and MCP access inside your own AI assistant. On the number that decides most purchases, Pro's per-word rate, the rise is small: $0.075 to $0.079 per 1,000 words on annual billing. That is why the score holds.

Pro on annual billing costs $0.079 per 1,000 words. Below roughly 490,000 words a month that is the cheapest rate on this ladder by more than three times, and it is the number to plan against.

Three things decide it for you. Volume, because Basic's 600-word cap splits your articles in half and its real rate is triple Pro's. Detector, because GPTZero and Writer.com results are good while Originality.ai at any real length is a documented failure no plan fixes. Workflow, because MCP is either the reason you buy Pro or a feature you will never open.

Use it if you write short marketing copy, your checker is GPTZero or Writer.com, and you can commit to Pro. Skip it if your work runs long against Originality.ai, your platform runs ZeroGPT, or your text faces Turnitin. If the smallest possible payment matters more than capacity per dollar, Undetectable AI starts at $9.99 a month for 10,000 words and is the cheaper way in, as the comparison above sets out. Whatever you choose, check the price on the vendor's own page before you pay, because the figures here changed twice in sixteen days, once when we fixed our own reading and once when the vendor raised its rates, and test it against the detector that decides before you commit to a year.