Flatten PDF

Permanently merge annotations, form fields, and stamps into the PDF content. Makes signatures and form data permanent. 100% private — all in your browser.

Drop a PDF file here or click to browse

Annotations, form fields, and stamps will be flattened

✅ PDF Flattened

All annotations and form fields have been permanently merged into the document.

Note: pdf-lib flattens form fields and most annotations. Complex annotation types (free text, rubber stamps) are preserved. For full flattening of all annotation types, consider using a desktop tool like Adobe Acrobat.

About Flatten PDF

Flatten PDF files to make annotations and form data permanent. Works entirely in your browser.

Make Signatures Permanent

After signing a PDF, flatten it so the signature can't be removed or tampered with.

Lock Form Data

Finished filling out a form? Flatten it to make the data permanent before sharing.

100% Private

Your PDF never leaves your browser. All processing via pdf-lib.

Instant Processing

Flattening happens locally in milliseconds. No waiting for server uploads.

📋 Common Use Cases

Finalize Signed Documents

Flatten signed PDFs to lock signatures and prevent accidental edits or modifications after signing.

Prepare Forms for Archival

Permanently embed filled form data into PDFs so saved values survive across different PDF readers.

Lock Annotations

Merge review comments, highlights, and markup into the document so they cannot be removed or altered.

Fix Rendering Issues

Resolve display problems caused by interactive elements not rendering correctly in certain PDF viewers.

🪜 How to Use This Tool

  1. Upload your PDF
    Drag and drop your PDF with annotations or form fields onto the upload area or browse to select it.
  2. Review document layers
    Optionally preview which elements are interactive and will be flattened into static content.
  3. Flatten the document
    Click flatten to permanently merge all form fields, annotations, and stamps into the PDF background.
  4. Download flattened PDF
    Save the final static PDF where all content is locked as a single non-editable layer.

📚 Related Guides

Frequently Asked Questions

Is this PDF tool really free?▼
Yes. Every PDF tool on iluv.tools is completely free. No signup, no account, no payment. Everything runs in your browser.
Are my PDF files uploaded to a server?▼
No. All PDF processing happens locally in your browser using the pdf-lib and PDF.js libraries. Your files never leave your device.
Do these PDF tools work offline?▼
Basic PDF tools (merge, split, compress, rotate, sign, watermark, protect, unlock, add page numbers, edit metadata, flatten, grayscale, crop, delete pages) work completely offline after the page loads. AI-powered tools like smart compression and PDF to Word require an internet connection.
Is there a file size limit?▼
Browser-based tools handle files up to ~100MB smoothly. Larger files may be slower depending on your device. For very large PDFs, try splitting them first, processing the parts, then merging.
Can I use these on mobile?▼
Yes. All PDF tools work on mobile browsers (iOS Safari, Android Chrome). Desktop is recommended for large files, but everything is functional on mobile.