Compress PDF
Reduce PDF file size by up to 80% — choose your compression level and download in seconds. No sign-up, no uploads.
Compress your PDF
PDF files only · up to 100 MB
Compress PDF files online for free with PDFCrush. Reduce your PDF file size by up to 80% without sacrificing quality. Choose from three compression levels and download in seconds. All processing happens locally in your browser — nothing is uploaded to any server.
How to Compress a PDF
Open the Compress PDF tool and drop in your PDF file — or click to select it. No sign-up required.
Choose your compression level: Extreme for smallest size, Recommended for best balance, or Less Compression to preserve maximum quality.
Optionally toggle image compression, metadata removal, and font optimization.
Click Download PDF — the compressed file is ready instantly.
Why choose PDFCrush for how to compress a pdf?
Up to 80% smaller file size — ideal for email, sharing, and storage
Smart per-page compression: text pages stay lossless, image pages compress deeply
Three presets plus four fine-tuning toggles for full control
100% browser-based — your files never leave your device
No watermarks, no sign-up, no file size limits (up to 100MB)
Works offline after the page loads — no internet connection needed
Common use cases
Reduce a PDF size to meet email attachment limits
Compress a PDF before uploading to an online form
Shrink a scanned document PDF for cloud storage
Reduce a presentation PDF for faster web sharing
Make a large invoice or report PDF smaller for archiving
Compress a portfolio PDF before sending to a client
Your privacy is protected
PDFCrush compression runs entirely in your browser using pdf-lib and a canvas rendering pipeline. Your files are never uploaded, stored, or transmitted. No third-party services have access to your documents. Your privacy is guaranteed by design.
Frequently asked questions
Will compressing a PDF make the text blurry or unreadable?
No. Our compression profiles target unneeded structural metadata and downsample oversized background graphics while leaving underlying vector text perfectly untouched.
How much file size can I reduce from a PDF?
You can typically reduce file sizes by 30% to 85%. High-resolution graphics compress deeply, while plain text layouts see minimal changes.
Will text remain selectable after running the PDF compressor?
Yes. Unlike crude tools that rasterize pages into flat images, our engine optimizes resources natively, keeping all underlying vector text fully searchable and selectable.
Can I compress a password protected PDF?
Yes, provided you enter the correct owner password. The browser engine uses local decryption routines to unlock the stream, apply compression, and save the file.
Is there a file size limit?
There is no rigid limit, but since compression runs in browser memory, documents larger than 100MB may be slower on older devices.
What image compression techniques are applied?
The compressor strips unneeded metadata, recompresses embedded JPEG images in-place, and optionally rasterizes image-heavy pages at optimal DPI — all while preserving vector text.
Why didn't my text-heavy PDF shrink much?
Text and vector elements are already highly efficient data structures. Significant size reduction occurs on documents containing high-resolution image assets.
Are my files private when using this tool?
Completely. All compression runs locally inside your browser sandbox. Your files never upload to any external server.
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