A 50MB PDF that won't send by email. An upload form that rejects your file for being too large. Sound familiar? PDF compression solves this — and you can do it completely free, in your browser, without installing any software.
Why PDFs get so large
PDFs become large mainly because of embedded images (especially scanned documents and photographs), embedded fonts, and unoptimized metadata. Compression works by reducing image resolution slightly and removing unnecessary data — without changing the text or layout.
Step-by-step: Compress a PDF for free
Go to Fourmeld PDF Tools
Open fourmeld.com/pdf-tools in any browser — Chrome, Safari, Firefox, Edge. Works on desktop and mobile.
Upload your PDF
Click Upload PDF or drag and drop your file. No file size limit — large PDFs work fine.
Select compress
Choose the Compress PDF option from the toolbar. You can select compression level: Standard (reduces size while keeping good quality) or High (maximum size reduction, slight quality trade-off).
Download your compressed PDF
Click Download. The compressed PDF downloads to your device. No watermark, no account, no cost.
How much can you compress a PDF?
| PDF Type | Original Size | After Compression | Reduction |
|---|---|---|---|
| Scanned document (images) | 20 MB | 2–4 MB | 80–90% |
| Presentation with photos | 10 MB | 2–3 MB | 70–80% |
| Report with charts | 5 MB | 1–2 MB | 60–75% |
| Text-only document | 500 KB | 400 KB | 10–20% |
When to use each compression level
Standard compression
Good for: emailing documents, sharing reports, uploading CVs and forms. The quality remains professional — you won't notice a difference reading on screen or printing.
High compression
Good for: archiving old documents where file size matters more than image sharpness, uploading to systems with very tight size limits (under 1MB), or web publishing where fast loading is priority.
Alternative: Compress during conversion
If you're creating a PDF from a Word document, compressing images before converting gives better results. Use Fourmeld's image compressor on your photos first, then create the PDF.
Compress Your PDF Free — Right Now
No software, no account, no watermark. Reduce PDF size in seconds.
Try Fourmeld PDF Tools Free →Frequently Asked Questions
Does compressing a PDF lose quality?
Standard compression preserves quality that's fine for screen viewing and most printing. High compression reduces image resolution slightly, but text and layout are unaffected.
What's the maximum email attachment size?
Gmail and Outlook both have a 25MB attachment limit. Most other email services are 10–25MB. Compressing to under 10MB ensures delivery across all email providers.
Can I compress a password-protected PDF?
No — you need to remove the password first (using Fourmeld's PDF unlock tool), then compress, then re-protect if needed.
Is compressing a PDF reversible?
No — keep your original file before compressing. Compression is permanent on the compressed copy. The original is never modified.