Compress PDF
Reduce file size while preserving high visual quality and typography.
Tailored Parameters
Fine-tune exact dimensions, qualities, ranges, or security tokens for this feature.
Instant Local Processing
Zero latency local computation directly in your browser session.
Same-Page Workflow
Re-run operations repeatedly without losing your active tool workspace.
Most of the weight in a typical PDF is images, and most of that is resolution nobody will ever see: a photograph captured at 600 dpi looks identical to one at 150 dpi once it is printed at postcard size. Compression downsamples and re-encodes those images while leaving text and vector graphics alone.
Because text is never rasterised, a compressed document stays selectable, searchable and sharp at any zoom. Only the pictures lose detail, and how much is your choice.
How it works
- 1Load the PDF. The current file size is shown so you can judge the result.
- 2Pick a compression level. Higher compression means smaller files and softer images. Start moderate and increase only if you need to.
- 3Compare and download. The before and after sizes are reported alongside the download.
When you need it
- Getting a scanned contract under an email attachment limit
- Reducing a photo-heavy brochure for web download
- Shrinking an archive of scans to save storage
- Meeting a portal's upload ceiling without splitting the document
Frequently asked questions
- Will my text become blurry?
- No. Text and vector artwork are left untouched; only bitmap images are re-encoded.
- Why did my file barely shrink?
- Because it was already efficient. A text-only document has almost no image data to reclaim, and a PDF that has already been compressed once has little left to give.
- Is the compression reversible?
- No. Discarded image detail cannot be recovered, so keep your original if it matters.
- Are my documents uploaded anywhere?
- No. Every tool in PDF41 runs inside your browser tab using WebAssembly and JavaScript. Your file is read from disk into memory, processed locally, and handed back as a download. It is never transmitted to a server, so there is nothing to intercept, retain, or delete afterwards.
- Does this work without an internet connection?
- Yes, once the page has loaded. The PDF engine, fonts and character maps are all served from this site rather than a third-party CDN, so an unstable connection or a locked-down corporate network does not stop the tool from working.
Similar tools to use
Complete your document workflow with these frequently paired tools.
Merge PDF
Combine multiple PDF files and images into a single cohesive document.
Grayscale
Convert full color PDF text and graphics to black and white.
Protect & Encrypt
Lock PDF with password encryption and custom access permissions.