PDF Flatten Tool

The PDF Flatten Tool bakes the interactive layer of a PDF — fillable form fields, checkboxes, dropdowns, highlights, sticky notes, stamps and ink markup — permanently into the page content, so the document can no longer be edited. Unlike other flatteners, it starts by x-raying your file: it lists every live object it finds, breaks it down by type, and draws the exact editable regions on top of each page thumbnail, so you can see what will change before you commit. Everything happens locally on your device, so your file is never uploaded to any server — safe for filled application forms, signed contracts, invoices, tax paperwork and medical records.

How to Flatten a PDF

1. Open your PDF. Drag the file onto the drop area or click Choose a PDF file. It is read in your browser and stays on your device. No form PDF handy? Click Try a sample fillable form to generate one instantly.
2. Read the x-ray report. The tool counts the fillable fields, comments and links it found and breaks them down by type — text fields, checkboxes, radio buttons, dropdowns, signature fields, highlights, sticky notes, stamps and more.
3. See the live layer on the page. Every editable region is outlined on the page thumbnails: teal for form fields, amber for markup, dashed blue for links. Untick Highlight the live layer to preview how the page looks once it is flat.
4. Choose what to bake in. Switch Flatten form fields and Flatten comments & markup on or off independently, and decide whether hyperlinks should stay clickable. Or switch to Rasterize to turn every page into an image.
5. Flatten and download. Click Flatten & Download PDF. The result tells you exactly how many items were baked in and how the file size changed.

What Makes This PDF Flattener Different

Smart Flatten vs Rasterize — Which Should You Pick?

When You Need to Flatten a PDF

Flattening is the step most people discover the hard way. You fill in an application form, email it, and the recipient opens it to find the fields empty — because their reader never rendered the field values. You send a signed quote and the client edits the price. You share a marked-up draft and the comments show up as clickable pop-ups that clutter the page or print as tiny icons. You upload a form to a portal that rejects "documents containing form fields". In every one of these cases the fix is the same: flatten the file so the answers and markup become ordinary page content that every reader, printer and upload system treats identically.

What Happens to Your Document

In Smart flatten mode each field's current appearance stream is painted into the page content at the exact position and size it occupied, following the appearance-stream rules in the PDF specification, and the interactive object is then removed. Annotations are handled the same way, so a yellow highlight stays yellow and an ink signature keeps every stroke. Because nothing is re-rendered as a picture, the text remains selectable and searchable and images keep their original resolution. Fields that carry no appearance at all — invisible buttons, hidden helper fields — are simply dropped, since they were never visible in any reader. The page count, page sizes and page order are untouched.