About Flatten PDF
FreeToolr's Flatten PDF tool makes completed form fields and visible PDF annotations part of the page. Use it for submitted forms, reviewed documents, marked-up plans, or records that should not keep separate editable fields. Choose form fields, annotations, or both. Form fields include text boxes, tick boxes, and choices. Annotations include comments, highlights, stamps, and drawings with a saved appearance. Links stay clickable after processing. Annotations without a saved appearance remain separate and appear in the report. The tool runs in your browser, so your PDF is never uploaded to a server. After processing, the flattened PDF downloads directly to your device. This gives you a clear result without sending a private form to an online service. Keep your original PDF because flattening is not reliably reversible.
How to use it
- 1Select a PDF from your device.
- 2Choose Form fields, Annotations, or both.
- 3Start the flattening process.
- 4Download the flattened PDF to your device.
Worked example
You select a 3-page PDF with two filled text boxes, one ticked box, and three highlighted passages. Choose both options. The downloaded PDF shows those values and highlights as page content, keeps its links clickable, and reports any annotations without a saved appearance.
How it works
Flattens a PDF: form field values (text boxes, tick boxes, choices) become part of the page and can no longer be edited, and annotations that have a saved appearance (comments, highlights, stamps, drawings) are merged into the pageYou can choose either or bothLinks stay clickableAnnotations without a saved appearance are left as they are and counted in the reportRuns in the browser: files are never uploadedResults download straight to the deviceSource: ISO 32000-1:2008, PDF 1.7 specificationAdobe PDF 1.7 specification copy. Last checked 4 November 2026.
What it is good for
- Keep links clickable after flattening.
- Choose form fields, annotations, or both.
- Process files in your browser without uploading them.
- Annotations without a saved appearance remain separate and are listed in the report.
- Flattening is not redaction, encryption, or a reliable way to reverse edits.
Questions people ask
What does flattening a PDF do?
It turns selected form field values and visible annotation appearances into page content. The selected fields and annotations can no longer be edited as separate objects.
Can I flatten form fields and annotations together?
Yes. You can choose form fields, annotations, or both before processing. Form fields include text boxes, tick boxes, and choices.
Will links still work after flattening?
Yes. Links stay clickable in the flattened PDF.
Are annotations without a saved appearance flattened?
No. They are left as they are and counted in the report. This can include annotations that have no saved visible appearance.
Does FreeToolr upload my PDF?
No. The tool runs in your browser, and files are never uploaded. The result downloads straight to your device.
Can I edit a flattened form again?
The flattened form values cannot be edited as separate fields. Keep the original PDF if you may need to change or refill it later.
Is flattening the same as redaction?
No. Flattening keeps visible information on the page. Redaction removes or permanently hides sensitive information, so use a dedicated redaction tool for private content.
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