Flatten PDF
Lock fillable form fields and annotations permanently into page appearance.
Drop your PDF here to flatten interactive form fields
Locks all form inputs and annotations permanently into page appearance.
No file size limit imposed by server • Processed locally in your browserFlattening Architecture & Notes:
Flattening converts fillable AcroForm fields and text annotations directly into permanent visual page content. Once flattened, form fields can no longer be edited or modified by PDF viewers. Dynamic XML-based XFA forms are not supported.
Your PDF is processed locally in your browser.
PDFSimplify processes documents on your device using client-side WebAssembly and Web Workers. No document data is transmitted to our servers or external cloud services during processing.
How Flatten PDF Works in Your Browser
Parses the document’s AcroForm dictionary locally in your browser using pdf-lib. Renders and burns existing field values into the visual page stream, removing interactive input widgets while preserving visual fidelity.
Why client-side processing is more private:
Unlike conventional online converters, your documents never traverse external networks to third-party processing servers. Everything happens inside your local machine’s memory.
How to Use Flatten PDF
Upload Form PDF
Select the filled PDF form to flatten.
Inspect Fields
Review detected interactive fields.
Flatten & Save
Download your permanently flattened PDF.
Key Features
Helpful Tips
- •Essential before submitting government, legal, or financial forms to ensure inputs cannot be changed.
Troubleshooting & Notes
- •Dynamic XML-based XFA forms created with proprietary software are not supported. Use standard AcroForms.
Frequently Asked Questions
Can a flattened PDF form be un-flattened later?↓
No. Flattening burns field text directly into the page stream, permanently removing the editable input structure.
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