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Flatten PDF

Flatten form fields, annotations, and layers into a static PDF.

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Tool settings

Processing runs in your browser where possible, so selected files do not leave this page.

Why use PDFlexa to Flatten PDF?

Locks form fields

Converts fillable fields, annotations, and layers into static, uneditable content.

Print-safe output

Ensures every annotation layer renders correctly when the file is printed.

One-way operation

Keep a copy of your original — flattening cannot be undone.

Free and instant

Flatten any PDF for free, with no account required.

How to Flatten PDF online — step by step

  1. Upload your PDF — Select the PDF containing form fields, annotations, or layers you want to lock down.
  2. Flatten the document — PDFlexa converts all interactive elements into static page content.
  3. Download the flattened PDF — Get a locked-down version that can no longer be edited or filled — keep a copy of the original first, since flattening isn't reversible.
Want a deeper guide? Read our step-by-step article on how to use this tool.
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Frequently asked questions about Flatten PDF

What does flattening a PDF do exactly?

Flattening converts all interactive elements — form fields, annotations, layers, and markup — into static page content. The result looks identical but cannot be edited or filled.

Why would I need to flatten a PDF?

Flatten a PDF before sharing to lock form fields and prevent editing. It is also required before printing to ensure all annotation layers are rendered correctly.

Is flattening reversible?

No. Once flattened, the interactive elements cannot be restored. Always keep a copy of the original file before flattening.

Is the Flatten PDF tool free?

Yes. Flatten any PDF for free, instantly, with no account or software required.