What is Flatten PDF?
Flatten PDF is a free online tool that bakes a PDF's interactive form fields into the page as static content and strips out links, sticky notes, highlights, and other annotations. It reports how many form fields and annotations a document has up front, and shows the before/after field count once processed. Everything happens entirely in your browser — your document is never uploaded to any server.
Common Use Cases
Lock in a Filled Form
Flatten a completed application or questionnaire so fillable fields can no longer be edited or re-filled.
Remove Sticky Notes & Highlights
Strip reviewer comments, highlight marks, and other annotation layers before sharing or publishing a document.
Remove Links Before Archiving
Take out clickable links so an archived or printed document has no lingering interactive elements.
QA Test Assets
Produce static, annotation-free copies of sample PDFs for test fixtures and content pipelines.
How to Use This Tool
- Upload a PDF file (up to 100 MB)
- Review the analysis — page count plus how many form fields and annotations it contains
- Click "Flatten PDF" and wait for processing to finish (a spinner shows while it works)
- Check the result card for the before/after field count and how many annotations were removed
- Download the flattened PDF, now with fields baked in and annotations removed
Related Tools
Learn More
- ISO 32000-2 — PDF Specification ISO 32000-2, the official specification of PDF forms and annotations.