Flatten a PDF — make annotations and forms permanent
Flatten interactive form fields, annotations, comments, and layers into the page content so recipients see them as permanent. Useful before final-version distribution.
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or browse from your computer · max 100 MB
A 'flattened' PDF is one where all interactive elements — form fields, annotations, comments, layers, JavaScript actions — have been baked permanently into the page content. After flattening, recipients can't change form values, remove comments, or toggle layer visibility. It's the standard final step before distributing a finalized version of any document that started life with editable elements. PDFOnly's flattener uses Ghostscript to re-render each page with all interactive content merged in, producing a clean static PDF that's safe to send.
How to flatten pdf step by step
- 1
Upload your PDF
Drop the PDF you want flattened. Files up to 100 MB free, 200 MB on Pro.
- 2
We flatten via Ghostscript
Each page is re-rendered with all interactive elements (form fields, annotations, layers) merged into the static page content. The result is a self-contained, non-interactive PDF.
- 3
Download the flattened PDF
Output looks identical to the original at the time of flattening, but all interactive elements are now permanent. Form values are visible as text but no longer editable. Annotations are visible as page content but no longer movable.
Why flatten pdf on PDFOnly
True flattening, not just locking
Some tools only set form fields to 'read-only' — recipients can still see them as form fields and the values can be changed via PDF editor tools. We re-render the page so the values become page content, indistinguishable from any other text on the page.
Removes JavaScript safely
Many PDFs from form generators include JavaScript actions that fire on open. Flattening removes them while preserving the visible content — your output works in PDF readers that block JS for security.
Output is a clean, portable PDF
After flattening, the PDF behaves like a static document scan — same file size or smaller, same visible content, no surprises in different readers.
What people use flatten pdf for
A few common scenarios. If your workflow looks like one of these, this tool is a good fit.
Finalize a filled-in form before sending
After filling a form, flatten it so the recipient can't accidentally (or intentionally) modify the entered values. Common with insurance forms, applications, and tax documents.
Lock down a contract draft
After negotiating with track changes and comments, flatten the final agreement so the signed version is permanent. Recipients see the comments only as visible page content, not as editable annotations.
Remove pre-press layers from a designed PDF
Designers ship PDFs with layers (cut lines, color guides, etc.) that print shops use. Flatten before sharing with a client so they don't see the production-only layers.
Strip JavaScript before distributing
Some PDF readers refuse to load JavaScript-bearing PDFs (security risk). Flatten removes the JS while preserving the visible content — making the file work everywhere.
What you get
- Flattens form fields — values become permanent text on the page
- Bakes annotations and comments into the page content
- Merges layers into a single visible layer
- Removes JavaScript actions that some readers refuse to load
- Output is a standard static PDF — opens identically everywhere
- Free, no signup, files auto-deleted in 1 hour
Frequently asked questions
Will the form values be visible after flattening?
Yes — whatever values were entered in the form are baked into the page as visible text. The 'fields' themselves disappear (no more text-input boxes) but the values remain visible in the same position they were displayed.
Can I unflatten a PDF to get the form back?
No — flattening is one-way. The form structure is destroyed when we render the page content. Keep your original PDF before flattening if you might need to re-edit later.
Will annotations and comments be removed or just locked?
They're rendered into the page content. Visually, they look the same. Functionally, they're now part of the page — not movable, not deletable, not editable. Sticky-note pop-ups become permanent yellow squares on the page.
Does flattening reduce file size?
Sometimes yes (when interactive elements were taking up significant structure overhead), sometimes no (when the rendered content takes more bytes than the editable structure did). Run through Compress PDF afterward if size matters.
What about digital signatures?
Cryptographic digital signatures are typically NOT flattened — they're a security feature that breaks if modified. Visual signature stamps (image overlays) are flattened normally. If your PDF has cryptographic signatures, flattening may invalidate them; verify before relying on the signature.
Can I flatten a password-protected PDF?
Not while encrypted. Use Unlock PDF first with the password, then flatten the unlocked version.
Will hyperlinks still work after flattening?
Yes — hyperlinks are a URI annotation type that survives flattening. Internal links (page-to-page navigation) stay clickable. External URL links stay clickable.
Ready to flatten pdf?
Free to use for the basics. Files are auto-deleted within an hour and never used to train AI.
Open Flatten PDF