Frequently Asked Questions
File Handling & Privacy
Are my files uploaded to your server?
Yes, PDF files are temporarily uploaded to our secure server for processing. We use PyMuPDF (a powerful PDF library) running on our backend to render pages and apply crop settings. However, files are automatically deleted within 1 hour and we never permanently store or analyze your content. See our Privacy Policy for details.
How long are my files stored?
Uploaded PDFs and generated image files are automatically deleted from our servers within 1 hour of upload. We do not create backups or archives of user files. Once you download your processed images and close the browser, all traces of your file are removed.
Do you read the content of my PDFs?
No. We only process the visual content of PDF pages to apply crop settings and generate images. We do not extract, read, or analyze text, metadata, or other content from your files. Your documents remain private.
What's the maximum file size I can upload?
The maximum PDF file size is 100MB. Large files may take longer to upload and process. For best performance, we recommend compressing very large PDFs before upload if possible, though this is not required.
Features & Usage
Can I crop left and right pages differently?
Yes! This is the main feature of our tool. Use the Left Page / Right Page radio buttons to switch between settings. You can set different trim percentages for each side to handle book bindings, varying margins, and page gutters. Red lines show left page crops, blue lines show right page crops.
What is Single Page Mode?
Single Page Mode is designed for PDFs where each page is a complete image (not a two-page spread). Enable this for:
- Book covers (front/back covers)
- Title pages
- Single-page documents
- Any PDF without left/right splits
When enabled, only the left page settings are used and red crop lines extend across the full width of the page.
What do the colored lines mean?
The colored lines show where your crops will be applied:
- Red lines: Left page crop boundaries
- Blue lines: Right page crop boundaries
These lines appear as dashed overlays on your preview image, showing exactly where the trim will occur.
How do I apply the same crop to all pages?
Once you've adjusted crop settings for a page, use these buttons:
- "Copy to All Pages": Applies current settings to every page in the PDF
- "Copy to Remaining": Applies current settings to all pages after the current one
This is useful when most pages have similar margins but a few (like covers) need different settings.
Can I preview changes before processing?
Yes! The preview area shows your PDF page with crop lines overlaid in real-time. As you adjust sliders, the lines update immediately. Use the "Previous" and "Next" buttons to navigate through pages and verify crops before processing.
Can I select which pages to export?
Absolutely! In the "Pages to Export" section, you can:
- Check/uncheck individual pages
- Use "Select All" to include all pages
- Use "Select None" to deselect everything, then manually choose pages
This is useful for skipping blank pages, removing unwanted content, or exporting only specific sections.
Export Options
What export formats are available?
You can export in four formats:
- JPG: Best for photographs and color images. Supports quality adjustment (1-100). Smaller file sizes with slight compression.
- PNG: Lossless format, perfect for text-heavy pages or when you need perfect quality. Larger file sizes but no quality loss.
- TIFF: Professional printing format with LZW compression. Used for archival and high-quality printing workflows.
- WebP: Modern web format with excellent compression. Smaller than JPG with similar quality. Supports quality adjustment.
What DPI should I use?
DPI (dots per inch) determines the resolution of exported images. Common settings:
- 72 DPI: Web/screen viewing only. Small file sizes but low quality for printing.
- 150 DPI: Good balance for digital reading on tablets/phones.
- 300 DPI: Standard for professional printing. Recommended for most use cases.
- 600 DPI: Very high quality for large format printing or archival purposes. Large file sizes.
What does the Quality slider do?
The Quality slider (1-100) appears for JPG and WebP formats. It controls compression:
- 85-100: Very high quality, minimal compression artifacts, larger files
- 70-84: Good quality for most uses, balanced file size
- Below 70: More compression, smaller files, may show visible quality loss
We recommend 90-95 for most purposes. PNG and TIFF don't use this setting as they're lossless.
How are exported files named?
Exported files are numbered sequentially (001, 002, 003, etc.) and include the file extension you chose (.jpg, .png, etc.). For example: 001.jpg, 002.jpg, 003.jpg. This ensures proper ordering when importing into eBook readers or other applications.
What format is the download?
All exported images are packaged into a single ZIP file for easy download. Extract the ZIP on your computer to access individual image files.
Technical Questions
Why does processing take so long?
Processing time depends on:
- PDF file size and number of pages
- DPI setting (higher DPI = longer processing time)
- Number of selected pages to export
- Current server load
Large PDFs at 600 DPI may take several minutes. For faster processing, use 150-300 DPI and only export pages you need.
What browsers are supported?
This tool works in all modern browsers:
- Google Chrome (recommended)
- Microsoft Edge
- Mozilla Firefox
- Apple Safari
JavaScript must be enabled. Internet Explorer is not supported.
Does this work on mobile devices?
Yes, the tool is responsive and works on tablets and phones. However, for best experience with large PDFs, we recommend using a desktop or laptop computer. Mobile connections may take longer to upload large files.
Why does my upload fail?
Common reasons for upload failures:
- File is larger than 100MB (compress or split the PDF first)
- File is corrupted or password-protected
- Poor internet connection
- File is not a valid PDF
If problems persist, try a different file or contact us.
Can I use this for commercial purposes?
You may use the tool for commercial purposes as long as you comply with our Terms of Service and you have the rights to the content you're processing. The tool itself is free to use, but you are responsible for ensuring you have permission to process and export any copyrighted material.
Copyright & Legal
Can I process copyrighted books?
You should only process PDFs that you own the copyright to or have permission to modify. This includes:
- Books you authored
- Public domain books (copyright expired)
- Content you've licensed with modification rights
- Personal scans you're legally allowed to digitize
Do not process copyrighted books you don't have rights to, even for personal use. Respect copyright laws in your jurisdiction.
Who owns the exported images?
You retain all rights to the images you export, subject to you having the right to process the source PDF. We claim no ownership over your exports. See our Terms of Service for details.
Support
Still have questions?
If you didn't find your answer here, please contact us. We're happy to help with any issues or questions about using the PDF Book Page Trimmer.
Is there a limit to how many PDFs I can process?
There is no hard limit on the number of PDFs you can process. However, we may implement rate limiting if we detect excessive or automated usage to ensure fair access for all users.
Do I need to create an account?
No! This tool requires no registration, login, or account creation. Simply visit the homepage, upload your PDF, and start trimming. Completely anonymous usage.