PDF Compressor
Free online PDF compressor. Reduce PDF file size by re-encoding embedded images — choose quality level, keep text sharp. Browser-based.
Click or drag PDF files here
Supports PDF format
PDF Compressor guide
Where the megabytes actually hide
Text in a PDF is tiny — a 100-page text-only report is often under 1 MB. The weight is in embedded images: scans at 600 DPI, photos dropped in at full resolution, screenshots pasted unresized. That is why this compressor targets images and leaves text untouched — it is re-encoding the actual source of the bloat.
Choosing a quality level
For email attachments (the 10-25 MB limit problem), medium quality is the right default — scanned text stays legible and photos lose only invisible detail. For archival copies, compress a duplicate, not your master file, and prefer lighter compression. Documents that must remain print-perfect (certificates, legal exhibits) deserve low compression or none.
| Setting | Resulting size | Text quality |
|---|---|---|
| Light | ≈ 12 MB | Indistinguishable from original |
| Medium | ≈ 6 MB | Crisp on screen and office print |
| Strong | ≈ 3 MB | Readable; fine print slightly softer |
When compression barely helps
Already-optimized PDFs (exported by modern software with image downsampling) and text/vector-only documents have little to squeeze — 5-10% is normal. If a PDF must get drastically smaller and resists compression, the fix is upstream: re-scan at 200-300 DPI instead of 600, or export from the source application with downsampling enabled.