Compress PDF
Shrink your PDF file size without visible quality loss.
or click to browse — supports PDF files up to 100MB
How to use
- 1 Drop or click to upload your file
- 2 Adjust options if shown
- 3 Click Run Tool
- 4 Download your result instantly
- ✓ Files up to 1GB
- ✓ Unlimited jobs/hour
- ✓ Batch processing
- ✓ Priority support
Files are processed securely and permanently deleted within 1 hour. We never store, read, or share your documents.
Why this works
Shrink a PDF so it slips under your email provider's attachment cap, fits an upload form, or stops bloating your Drive. Compression runs in your browser session and your file is auto-deleted within an hour.
PDFs balloon for predictable reasons: high-resolution scans, full-colour images embedded at print quality, fonts subsetted multiple times across merged documents. Most of that weight is invisible to the reader. A typical 12 MB scanned contract drops to under 2 MB without any visible loss of text legibility — the optical character data only needs to be readable, not magazine-printable.
We expose three compression levels. Recommended is the right choice 95% of the time: images downsampled to 150 DPI, fonts subsetted, embedded JavaScript stripped. Maximum compression drops image quality further (down to roughly 96 DPI) and is the right choice when you're hitting a hard cap — Gmail's 25 MB attachment limit, an HR portal's 5 MB resume cap, a court e-filing system's 10 MB ceiling. Low compression keeps image quality close to the original — pick it when the PDF will be printed or when the recipient is going to zoom into figures.
If your PDF is a scanned document — phone-camera shots of a contract, a scanner dump from your office multifunction — the biggest single win is usually OCR + compression run together. Use the OCR tool first to make the document searchable, then compress: the text layer adds almost nothing to the file size but transforms what the recipient can do with the document.
Files are processed on our servers (powered by Stirling-PDF) over an encrypted connection and removed within one hour. No watermark is applied. No account is required. Compression is free for files up to the size cap on your current plan — most visitors never hit it.
How it works
-
1Upload your PDFDrop your file into the upload box above or click to browse. We accept any standard PDF — scanned, born-digital, or one you exported from Word.
-
2Pick a compression levelRecommended is the right default. Use Maximum if you need to hit a hard size cap (like Gmail's 25 MB limit). Use Low if the document will be printed.
-
3Run the compressionPress Compress. Most documents finish in 3–8 seconds. Scanned PDFs over 50 pages take a little longer.
-
4Download the smaller fileYou'll see the original size, the new size, and the percentage saved. Click Download to save it. Files are auto-deleted from our servers within one hour.
Real-world uses
Job seekers
Resume + portfolio combined exceeds the careers-page upload cap (often 5 MB). Compress before uploading.
Sales reps
Customer decks with high-res screenshots and product photos balloon past 50 MB. Recommended compression preserves the look at a fraction of the size.
Mortgage applicants
Lenders typically cap each supporting document at 10 MB. Bank statements scanned in colour blow past this — compression solves it.
Law firms
Court e-filing portals impose hard size limits (often 10 MB per filing). Maximum compression keeps you under the cap without splitting the document.
Common questions
How small can you compress a PDF?
In practice, a colour scan typically drops 60–80%. A born-digital PDF (Word export, Pages export) drops 20–40% — the source was already efficient. There's a floor: the text, fonts and document structure each have a minimum encoded size, so a 30-page text-only PDF won't go below roughly 200 KB no matter the compression level.
Will compression hurt the quality?
At the Recommended level, almost never visibly. Images are downsampled to 150 DPI, which is the resolution most desktop screens render at. Maximum compression pushes images down to roughly 96 DPI — text is still crisp, but you'll see softening if you zoom into a photograph. Low keeps near-original quality.
Why is my PDF too big for Gmail?
Gmail allows attachments up to 25 MB. Above that it auto-converts the file to a Google Drive link, which some recipients (corporate firewalls, mailing lists) reject. The Recommended setting will get most documents below 25 MB; if not, Maximum compression almost always succeeds for documents up to ~50 MB original size.
Are my files private?
Yes. Uploads travel over HTTPS. Files are processed on our servers and removed within one hour. We don't inspect, store, or share document content. No human eyes ever see your files.
Do you add a watermark?
No. PDFRun never adds a watermark on the free tier, unlike some competitors that watermark output after a daily quota or below a paid plan.
Can I compress multiple PDFs at once?
Yes — drag in multiple files, or upload a ZIP of PDFs. The output comes back as a ZIP with the same filenames, each compressed individually. Pro plans have higher batch limits.
What's the largest file I can upload?
Free accounts upload up to 25 MB per file. Pro lifts this to 500 MB. The maximum is also displayed in the badge at the top of the page.