Compress PDF Online — Free, Fast & Secure
Shrink PDFs by up to 90% without losing quality. Batch upload, three compression levels, files up to 100MB — no signup, no watermarks, no drama.
Drop PDFs here to compress
Drag & drop, or click below — up to 100MB per file, batch supported.
Choose compression level
Change it any time before you compress.
How to compress a PDF
Four steps. Three clicks. Zero learning curve.
- 1Upload your PDF
Drag and drop one or many PDFs into the drop zone, or click Browse. Files up to 100MB are supported.
- 2Choose a compression level
Pick Low for best quality, Recommended for a great balance, or Extreme for the smallest file size.
- 3Compress
Hit Compress. Progress bars show real-time upload and processing status — no frozen spinners.
- 4Download
Grab each compressed PDF individually, or download the whole batch as a single ZIP.
Why compress a PDF?
A smaller PDF is a friendlier PDF. Here’s where compression pays off the most.
Gmail, Outlook and most email providers cap attachments around 20–25MB. Compression fits fat PDFs through the tiny door.
Most job boards and university portals cap uploads at 5–10MB per file. Shrink your resume, transcripts or portfolio without cropping content.
Smaller PDFs upload in seconds on slow or mobile connections — great for client portals, government forms and CMS uploads.
A well-compressed PDF can be up to 90% smaller. Multiply that across a Dropbox, Drive or team folder — the savings add up fast.
Messaging apps struggle with big documents. Compress once, send anywhere, without frustrated “file too large” errors.
Compression levels, explained
Not sure which one to pick? Here’s exactly what happens under the hood at each level — in plain English, no jargon.
Light compression that keeps images sharp and text crisp. Best when the PDF will be printed, signed, or archived. Expect roughly 15–35% size reduction on image-heavy files.
Our default. Downsamples embedded images to around 150 DPI and applies smart image compression. Great screen readability with typically 50–80% smaller file size.
Downsamples images to around 72 DPI and applies aggressive JPEG compression. Text stays sharp. Pick this when you must hit a strict upload cap — typical reductions of 70–95%.
Your documents are yours.
We built CompressPdf because most “free” PDF tools quietly monetise your files. We don’t. No accounts. No third-party sharing. No training on your data. Files are compressed in an isolated environment and permanently erased within 60 minutes.
- Auto-delete after 1 hour
Every uploaded and compressed file is wiped from disk within 60 minutes. No archival, no backups.
- Encrypted transfer
Uploads and downloads run over HTTPS end-to-end. Your PDFs never travel in the clear.
- No third-party sharing
We do not share, sell, index, or train models on your documents. Ever.
Frequently asked questions
Everything you might want to know before you upload.
When compression helps — and when it won’t
Compression works best on PDFs that contain scans, photos, or heavy images — they can often shrink 70–95%. PDFs that are mostly plain text or vector graphics may already be near-optimal, so the win is smaller. If your file barely shrinks after Extreme, that’s not a bug — it means the PDF is already efficient.
Ready to shrink that PDF?
No email required. No watermarks. Just drop your file and go.