Does my file get uploaded?

No. The PDF is read and flattened entirely in your browser, on your own device. The file never leaves your computer and never reaches a server. That matters more here than almost anywhere: the forms people flatten are the filled-in ones, carrying names, dates, account numbers and signatures.

What exactly does flattening do?

It turns the interactive layer into ordinary page content. A filled form field stops being a field and becomes the drawn text of its value; a comment or stamp stops being a movable annotation and becomes part of the page. Nothing can be typed over, cleared, or dragged away afterwards. The rest of the document is untouched — no page is rasterised, so text stays selectable and searchable.

Does it flatten comments and stamps, or only form fields?

Both. Form fields are flattened, and so are markup annotations — comments, stamps, highlights and drawn shapes — as long as they carry a stored appearance, which is what a PDF reader saves when someone marks a document up in Preview or Acrobat. The tool shows you the counts for the file you picked before you download anything.

Is there anything it can't flatten?

Yes, and it tells you. An annotation with no stored appearance can't be baked in faithfully — synthesising one would mean guessing what the original reader drew, and guessing wrong would silently alter your document. Those are left in the file, still editable, and the count is shown on screen. Links are also kept, since a link has no visible body of its own and flattening one would only break the link.

What if the PDF has nothing to flatten?

The tool says so and produces no file. It does not re-save an unchanged document and present it as flattened — a file that looks processed but isn't is worse than a clear refusal, because you'd send it on believing it was locked.

Can the values be recovered afterwards?

Not through the form. The field is gone and its value is drawn content, so no reader will offer to edit or clear it. Flattening is about permanence, not secrecy — the text is still text on the page and can still be selected or copied. If you need content genuinely removed rather than locked, use Redact PDF, which destroys the underlying content instead of fixing it in place.

PDF Tools

Flatten PDF

Bake a PDF's filled form fields, comments and stamps into the page so they can no longer be edited or cleared — entirely in your browser. The file is never uploaded. No account, no email.

Frequently asked questions

Does my file get uploaded?: No. The PDF is read and flattened entirely in your browser, on your own device. The file never leaves your computer and never reaches a server. That matters more here than almost anywhere: the forms people flatten are the filled-in ones, carrying names, dates, account numbers and signatures.
What exactly does flattening do?: It turns the interactive layer into ordinary page content. A filled form field stops being a field and becomes the drawn text of its value; a comment or stamp stops being a movable annotation and becomes part of the page. Nothing can be typed over, cleared, or dragged away afterwards. The rest of the document is untouched — no page is rasterised, so text stays selectable and searchable.
Does it flatten comments and stamps, or only form fields?: Both. Form fields are flattened, and so are markup annotations — comments, stamps, highlights and drawn shapes — as long as they carry a stored appearance, which is what a PDF reader saves when someone marks a document up in Preview or Acrobat. The tool shows you the counts for the file you picked before you download anything.
Is there anything it can't flatten?: Yes, and it tells you. An annotation with no stored appearance can't be baked in faithfully — synthesising one would mean guessing what the original reader drew, and guessing wrong would silently alter your document. Those are left in the file, still editable, and the count is shown on screen. Links are also kept, since a link has no visible body of its own and flattening one would only break the link.
What if the PDF has nothing to flatten?: The tool says so and produces no file. It does not re-save an unchanged document and present it as flattened — a file that looks processed but isn't is worse than a clear refusal, because you'd send it on believing it was locked.
Can the values be recovered afterwards?: Not through the form. The field is gone and its value is drawn content, so no reader will offer to edit or clear it. Flattening is about permanence, not secrecy — the text is still text on the page and can still be selected or copied. If you need content genuinely removed rather than locked, use Redact PDF, which destroys the underlying content instead of fixing it in place.

Frequently asked questions

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