How to Compress PDF - Reduce PDF Size Online
Compress PDF files online for free. Reduce file size without losing quality. Secure, client-side processing.
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Select or drag and drop your file to start compress pdf online. No account or software install required.
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FormatWiz processes compress pdf in your browser—fast, private, and completely free.
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Why Use FormatWiz for Compress PDF?
Free, secure Compress PDF with client-side processing—no signup required.
Efficient & Fast
Optimize large files in seconds.
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Files are processed in your browser.
Smart Optimization
Balances size and quality perfectly.
100% Secure
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Lightning Fast
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Where PDF file size actually comes from
Text in a PDF is tiny — a whole novel fits in under a megabyte. Nearly all the weight sits in embedded images, which is why a ten-page scan can outweigh a three-hundred-page manual and why compression results vary so much between documents.
| Document type | Typical reduction |
|---|---|
| Scanned pages | 50–80% |
| Brochures & photo reports | 40–70% |
| Slide-deck exports | 30–60% |
| Text-only documents | 0–15% |
| Already-optimised files | Minimal |
Typical jobs people use this for
- Getting a scanned lease under a 25 MB email attachment cap
- Shrinking a portfolio PDF for an application portal
- Reducing a photographed receipt bundle before archiving
When this is the wrong tool
If the file is mostly text and already small, compression cannot conjure savings. And when a single document must go far below its natural size, splitting it into parts keeps quality where extreme compression would visibly degrade the images.
Frequently Asked Questions
How much smaller will my PDF get?
Will the text become blurry?
Why did my file barely shrink?
Is it good enough for email attachments?
Does my document get uploaded to a server?
Guides & Tutorials
Step-by-step guides for every FormatWiz tool — free, private, and browser-based.
Learn how to compress PDF online free and reduce file size while keeping text sharp — no signup, with secure client-side processing in your browser.
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Read guideLearn how to edit PDF online free, fill forms, and add a signature in your browser — no signup, with your file staying private on your own device.
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