Flatten PDF Online
Lock form fields, annotations, and layers into a flat, non-editable PDF. Perfect for submissions, archiving, and sharing final documents.
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Supported formats: .pdf
Flattening a PDF merges all form fields, annotations, comments, and interactive layers into the page itself. The result is a clean, static PDF that displays consistently across every device and viewer — no more missing data or blank fields.
- ✓ Lock filled form fields so they cannot be edited
- ✓ Merge annotations and comments into the page
- ✓ Fix blank fields that appear in some PDF viewers
- ✓ Works on Mac, Windows, iOS, Android, and Linux
- ✓ No installation — flatten PDFs in your browser
Submit Forms Without Blank Fields
Filled out a PDF form but the recipient sees empty fields? This happens when form data isn't embedded in the page. Flattening locks everything into place so it displays correctly everywhere.
Finalize Signed Documents
After signing a PDF, flatten it to prevent further edits. Signatures, form data, and annotations become permanent parts of the document — perfect for contracts and legal submissions.
Archive PDFs for Long-Term Storage
Flattened PDFs are converted to PDF/A format, the international standard for long-term document archiving. This ensures your documents remain readable years from now.
How to Flatten a PDF
Upload or drag and drop your PDF into OmnisPDF.
Click Flatten PDF — all fields and annotations are merged into the page.
Download your flattened, non-editable PDF.
Frequently Asked Questions
What does it mean to flatten a PDF?
Flattening a PDF merges all interactive elements — form fields, annotations, comments, and layers — into the page content. The result is a static, non-editable PDF that looks the same everywhere.
When should I flatten a PDF?
Flatten a PDF before submitting forms, sharing signed documents, archiving records, or when a recipient sees blank fields. Flattening ensures the content is locked and visible.
Will flattening change how my PDF looks?
No. The visual appearance stays the same. Flattening only removes the ability to edit form fields, annotations, and interactive elements.
Can I flatten a PDF with filled-in form fields?
Yes. All filled-in data is preserved and becomes part of the page content. The fields just can no longer be edited.
Can I flatten a PDF on my phone?
Yes. OmnisPDF works in mobile browsers — upload, flatten, and download on iPhone or Android.
Is it free to flatten a PDF?
Yes. Free accounts get 10 conversions per day. Pro accounts get unlimited usage.