Flatten a PDF
Choose what becomes permanent
Flattening your PDF
Flattening complete
Details
Make PDF form fields and visible annotations permanent without uploading the file. The tool counts fields, marks, links, signatures and optional-content layers first, so you choose what becomes permanent before anything changes. Links stay clickable, marks without a usable appearance are reported rather than dropped, and page count, page geometry and original selectable text are checked before download.
How to flatten a PDF
-
Choose a PDF
Choose a PDF or drop it onto the page. The file stays in this browser tab.
-
Review what was found
The tool counts form fields, visible annotation marks, links, signatures and optional-content layers before it changes anything.
-
Choose what becomes permanent
Keep form fields and their current values, visible annotation marks or both selected. Links stay clickable. Marks without a usable appearance stay unchanged.
-
Download the checked file
The output is reopened. Its page count, page geometry, original selectable text and remaining interactive elements must match the requested result.
What stays unchanged
Links stay interactive. Annotation objects without a usable normal appearance stay in the PDF because removing them could erase visible information. Optional-content layers are reported but not flattened.
Flattening changes the document bytes, so it invalidates existing digital signatures. It does not remove passwords; unlock a protected PDF first.
Before you flatten
Flattening goes one way. Once a field is permanent, nobody can change the answer inside it, including you, so keep the original file. Fill out a PDF form covers completing the fields first, and How to edit a PDF covers what a browser tool can still change once the flatten has run.
Questions about flattening PDFs
- What does flattening a PDF do?
- It draws form field appearances and visible annotation marks into the page content, then removes the interactive objects it made permanent.
- Does text stay selectable?
- Yes. The existing page content is not rendered into a picture. The output must retain at least 98% of the original non-space selectable characters.
- Do links still work?
- Yes. Link annotations are kept rather than flattened.
- What happens to comments without a visible appearance?
- They stay unchanged. The result names how many could not be made permanent safely.
- Does this flatten PDF layers?
- No. Optional-content layers are detected and reported, but this version does not merge their visibility states into page content.
- What happens to digital signatures?
- Changing a signed PDF invalidates its existing signatures. The tool requires explicit confirmation before it flattens a signed file.
- Does the PDF leave my browser?
- No. Inspection, rewriting and verification all run in this browser tab.
The other pdfpix tools
All 30 of them run in a browser tab like this one. Each reads its own output back and checks it before offering the download, and none of them needs an account.
- Merge PDFs Several PDFs into one
- Organize pages Split, reorder, delete
- Rotate & crop Pages upright, margins cut
- Images to PDF JPG and PNG
- HEIC to PDF Open iPhone photos
- TIFF to PDF Open multi-page scans
- WebP to PDF Open images saved from the web
- BMP to PDF Open bitmap images
- Privacy scan Remove private metadata
- Protect & unlock Add or remove a password
- Repair PDF Rebuild a broken file
- Compress PDF Hit a size target
- PDF size breakdown See where every byte goes
- Print preflight Check a PDF before press
- PDF to images Export JPG or PNG
- PDF to TIFF One multi-page image file
- Extract images Save original pictures
- PDF to Markdown Keep the document structure
- Markdown to PDF Make a verified document
- PDF to CSV Extract a table
- PDF to Excel One table per sheet
- Sign PDF Draw, type or upload
- Stamp PDF Number, label, watermark
- Compare PDFs Words and pages that changed
- Fill PDF form Complete existing fields
- Create PDF form Add fillable fields
- N-up & booklet Print several pages per sheet
- Comic archive CBZ to PDF and back
- Redact PDF Destroy marked content
- Redaction checker Find text under black boxes
Where to go next
- Add page numbers to PDF Put page numbers, a header, a footer, a watermark or Bates numbers on a PDF.
- Password protect PDF Put a password on a PDF before you send it.
- Merge PDF Join several PDFs into one file in the order you choose.
- How it works Understand what runs in the browser tab, what it checks, and what it never sends.