An unlimited free AI detector can allow unlimited checks and still cap the length of each check. Scribbr, for example, advertises unlimited checks and up to 1,200 words per submission. A 3,100-word draft therefore needs at least three submissions at that cap. Scribbr's published limits
Before you split a document, check three things: the maximum text allowed in one request, how many checks the free option covers, and which report details you will actually be able to see.
Count checks before you paste
- 3,100 words
- Count the text you intend to submit, including any notes or references you leave in.
- 1,200 per check
- Compare the count with the documented per-submission limit.
- At least 3 checks
- Choose breaks at natural section boundaries and verify each section fits.
humanizeink.com
Read what “unlimited” applies to
Scroll to see all columns
| Limit | Where to look | How it affects a long draft |
|---|---|---|
| Per submission | The field counter and help text | Determines how many pieces you need for one pass. |
| Free scans or credits | Pricing and free-plan details | Determines whether you can cover all pieces and repeat a scan. |
| Report detail | Result screen and plan comparison | Determines whether you can inspect exact passages or only an overall result. |
| File upload and language | Document requirements | Determines whether your file and its text can be analyzed as intended. |
Read the help for the feature you actually opened. A browser paste checker can have different limits from a document upload or an API, even on the same site.
Calculate the number of checks
Suppose a draft has 3,100 eligible words and the box holds 1,200. Two checks cover up to 2,400 words. A third is enough for the remaining 700. If the document has sections of 1,150, 900, and 1,050 words, those three sections fit separately. For six 1,200-word chapters, a full pass takes six checks. Rescanning the whole draft after a revision uses six more.
Divide the total by the per-check limit and round up. That’s the minimum number of checks. If you choose to split at headings or keep a paragraph intact, the number may be higher. Use the counter on the actual checker to confirm what it considers a word. If it limits characters, compare character counts in the same units instead.
Keep context when you split a document
Separate at a heading or paragraph break and label each part in your own notes. Write down which version you submitted and the approximate length of each part. Compare the result with that section of the draft. If several sections refer to the same term or quotation, check the relevant context in the whole document before changing wording.
Do not average the reported percentages unless you know they use the same eligible text and that the vendor defines a valid aggregation method. A result for a piece of text can behave differently from a single full-document result. If the decision requires the whole document, use an approved service that supports that document length and file type under its own terms.
Make the free-check decision
If all you need is a quick look at a short, non-sensitive example, a public paste checker may suffice. For regular long-document review, compare the limits with your expected volume and read the service's handling of submitted text. For a question about who wrote a document, preserve draft history and sources. The report can help you identify where to look, while the history shows how the writing developed.
Frequently asked questions
Does unlimited free mean one scan can take a whole book?
Check the per-submission length. Unlimited checks can still require splitting a long document into several submissions.
How many 1,200-word scans do I need for 4,000 words?
At least four. Three cover at most 3,600 words. Section breaks can make you need additional scans.
Should I include the bibliography or quoted passages?
Read the provider’s rules about eligible text before submitting. Keep the source document unchanged and record what you included.
Can I average separate percentages into a manuscript score?
Use the results alongside each section unless the checker documents a valid whole-document calculation.
What if each scan is free but highlights require payment?
Decide whether the basic report answers your question before scanning all the sections. Read the feature comparison if you need sentence-level detail.