Shrink large PDFs without losing the details. Pick screen, eBook, or print quality, drop your file, and download a smaller copy. Compression runs on Culacc's server in Germany using Ghostscript — typical reductions are 60–90% — and the original is deleted the moment the compressed copy returns to your browser. No account required.
| Preset | Typical reduction | Best for |
|---|---|---|
| Screen | 80–95% | Web previews, email attachments, anything viewed only on a screen |
| eBook | 60–85% | Most everyday PDFs — readable on screen and print, balanced quality |
| 30–60% | Archival, professional printing, anything where image fidelity matters |
The image compressor and PDF merger on this site run entirely in your browser. PDF compression doesn't, and there's a good reason. To shrink a PDF meaningfully you have to re-encode its embedded image streams — that's where 90% of the file size lives. Browser PDF engines (pdf.js, pdf-lib) can't do that re-encoding; only a real PDF processor like Ghostscript can. Doing this in the browser would result in tiny savings that aren't worth the trouble.
So we made the trade-off: the file is sent to our server in Germany over HTTPS, compressed there, and the original is deleted immediately when the compressed copy returns. The result is real, useful compression — typically 60–90% smaller — instead of marginal browser-side savings.
On Culacc's EU server in Germany. The file is sent over HTTPS, compressed with Ghostscript, and the original is deleted as soon as the compressed copy returns to your browser. There is no persistent storage for free tool uploads.
Most PDFs shrink 60–90% on the eBook preset without visible quality loss. Text-heavy PDFs already compress well; the big savings come from PDFs with embedded images, scans, or large diagrams.
On the eBook preset, no — text stays sharp and images remain perfectly readable. The Screen preset is aggressive enough that high-resolution images start to look softer, which is fine for web previews but not ideal if you'll print the PDF later.
Currently 50 MB per file on the free tool. Larger files would benefit from a Culacc account where compression runs on your own quota with no per-file cap.
Yes. Text stays as real text — you can still copy, select, and search inside the compressed PDF. Compression only re-encodes images and removes redundant data, not the text layer.
Yes — make a free Culacc account (5 GB, every feature unlocked) and use the Save to my Culacc button. The compressed PDF lands in your storage, available on every device you sync.