Flatten PDF

Merge interactive form fields into the page so they can't be edited — right in your browser, nothing uploaded.

Flatten merges interactive form fields into the page so they can no longer be edited or filled — useful before sharing a completed form. If the PDF has no form fields, it is simply re-saved unchanged. This does not rasterize the page, so text stays sharp.

Drop a PDF here, or click to browse .pdf · stays on your device

How to Flatten a PDF

Two steps, all in your browser.

1

Add your PDF

Drag in a PDF, or click the box to browse. The file stays on your device — nothing is uploaded to any server.

2

Flatten and download

Click Flatten PDF. If the file has fillable form fields, pdf-lib merges them into the page so they can't be edited or filled again. If there are no form fields, the file is re-saved unchanged. Need a smaller file instead? Try Compress PDF.

Frequently Asked Questions

What does flattening a PDF actually do?
It merges interactive form fields into the page itself. Any fillable text boxes, checkboxes or dropdowns are converted into fixed page content showing their current values, using pdf-lib's form-flatten feature, so the fields can no longer be edited or filled in — useful before sharing a completed form.
How is Flatten different from Compress PDF?
Flatten only touches interactive form fields and keeps everything else exactly as it is — no rasterizing, no quality loss, text stays sharp and selectable. Compress PDF instead renders every page to a compressed image to shrink file size, which makes text no longer selectable. Use Flatten to lock a filled-in form; use Compress PDF to shrink a large file.
What happens if my PDF doesn't have any form fields?
Nothing to flatten means the file is simply re-saved unchanged. You still get a valid, downloadable PDF and a clear "no form fields found" message instead of an error.
Does flattening rasterize the PDF or reduce quality?
No. Flattening only merges form-field appearances into the page's content stream — it does not render pages to images, so vector text and graphics stay exactly as sharp as the original.
Is my PDF uploaded anywhere?
No. The PDF is loaded and flattened entirely in your browser with pdf-lib, and the result never leaves your device until you choose to download it. Nothing is uploaded, logged or stored.