Merge form fields, annotations, and layers into the page content.
Your file stays private. All processing happens locally in your browser using pdf-lib — no uploads, no servers. Flatten your PDF to make form fields and annotations permanent, then download instantly.
Flatten a PDF to merge form fields, annotations, comments, and layers into the page content. Once flattened, the content becomes permanent and cannot be edited. This is useful for finalizing filled forms, locking annotations, or preparing documents for printing.
All processing happens in your browser using pdf-lib — no uploads, no servers, complete privacy. Upload your PDF and download the flattened version instantly.
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Flattening a PDF merges interactive form fields into the page itself, so their values become permanent, fixed content. Instead of layered data that each viewer has to interpret, you get a stable document that renders identically everywhere it is opened. This tool performs the flatten in your browser with pdf-lib, meaning the file never leaves your device and the result is ready to download in seconds.
A PDF with a fillable form keeps its data in a separate interactive layer. Every time the file is opened, the viewer has to draw that layer on top of the page, and how it looks can vary from one program to the next. Flattening collapses that layer into the page graphics, so the values you see are exactly the values that print, export, and archive. It is the difference between a working draft and a finished, locked document.
The tool loads your file, flattens the form if one is present, and saves it back out. Documents without any form fields pass through unchanged and still download normally.
Flattening belongs at the end of a workflow rather than the start. Fill in a form, add any final touches, and flatten the document before you send it out, publish it, or store it for the long term. Finished applications, finalized invoices, and signed agreements are classic candidates, because once the data is locked into the page, nobody can quietly change what was submitted.
For the same reason, flattening is useful before handing a file to someone who does not have proper PDF software. A flattened document always shows its true content, even in lightweight viewers or online previews.
Pro tip
Flatten a copy, not your working file. Keep the interactive version for yourself so you can still update it later, and share the flattened file with anyone who should receive a finished, read-only document.
Because flattening runs on your own machine, confidential paperwork never travels to a server. Free users can flatten files up to 10 MB, and a Premium subscription raises the limit to 100 MB while removing the wait time. Whatever your file, the result is produced entirely in your browser and delivered straight to your downloads.