Auto-Trim Whitespace
OptimizeDetects the actual content area on each page and automatically crops away surrounding whitespace — perfect for scanned books and screenshots.
How to use Auto-Trim Whitespace
- Open this page in any modern web browser — no download or installation required.
- Click Add file or drag and drop your PDF onto the drop zone.
- Adjust the available settings to fit your needs.
- Click the action button and save the processed file — the result is ready instantly.
Files never leave your browser. No upload to any server.
Processing runs locally on your device. No queues, no waiting.
No signup, no watermarks, no limits. Use as many times as you like.
Why use Auto-Trim Whitespace on PDF Modern?
PDF Modern’s auto-trim whitespace tool processes your file entirely within your web browser using modern WebAssembly technology. Unlike traditional online PDF services that require uploading your documents to remote servers, your files never leave your device — ensuring complete privacy and security. Processing happens at the full speed of your CPU, not limited by upload or download bandwidth, so even large files are handled in seconds. There are no file-size restrictions, no daily usage caps, no watermarks on output, and no account creation needed. It is a fully free, open tool built for everyday document workflows at home, school or the office.
Frequently asked questions
How does auto-detect work?
Each page is rendered to a canvas and scanned for any non-white pixel. The crop box is set to the tightest bounding rectangle plus a small safety margin.
Will it remove anything important?
No — only blank-looking margins are trimmed. The original content is never altered, just the visible crop.