Flatten PDF
Make form fields uneditable, or rasterize every page to lock its visible appearance. Processing stays in your browser.
Lock down a PDF so it can't be accidentally edited: forms-only flattening converts fillable fields into permanent text while keeping selectable text and links intact, and full flattening rasterizes every page into a locked image. Useful for finalizing a filled-out form before sending it, or making sure a document's exact visible layout can't be altered by the recipient. Both modes run locally with pdf-lib.
Loading tool
How it works
- 01
Upload your PDF.
- 02
Choose Forms only or Full flattening.
- 03
Click Flatten and download the result.
Details
- Category
- Documents & PDF
- Formats
- Runs
- In your browser
- Files uploaded
- No
- Cost per run
- Free
- Sign-in
- Not required
- Works offline
- Yes, once loaded
Last updated 2026-08-03
Common questions
Which mode should I use?
Forms only preserves selectable text and links. Full flattening converts each page to an image, which also locks annotations but removes selectable text and links.
Does flattening redact hidden information?
Full flattening keeps only the rendered page appearance, but this is not a substitute for reviewing a document with a dedicated redaction workflow.
Does it upload my PDF?
No - flattening runs entirely in your browser using pdf-lib.
Can I still fill the form after flattening?
No - flattening is intentionally permanent. Keep an unflattened copy if you need to edit the form fields again later.