Compress PDF Online

Upload a PDF to preview it, then pick Low (−25%), Medium (−50%) or High (−75%) — each option shows its estimated output size before you compress. The file stays a real PDF with the same pages and layout; only the size shrinks.

🔒 Files never leave your browser

Drag & drop your file here

or click to browse your device

Why compress a PDF?

Big PDFs are a pain: email servers reject attachments over 20–25 MB, upload forms time out, and sharing a 60 MB scan over chat takes forever. To compress pdf files the smart way, you need to shrink them without turning the text into a blurry mess — which is exactly what GroPDF's compressor does. It rebuilds your document with optimized images and cleaned-up internals, so the file gets much smaller while staying perfectly readable.

How to compress a PDF

Drop your PDF onto the page (or click to browse). It never leaves your device — compression runs locally in your browser — and you'll see a preview of it right away.
Pick a compression level: Low shrinks the file by about 25% with near-original quality, Medium by about 50%, High by about 75%. Each option shows its estimated output size before you commit.
Click the level you want and wait a few seconds while the tool processes your pages.
Download your smaller PDF and check it looks right. Not happy? Re-run with a different level — it's free and unlimited.

Which compression level should you choose?

Low targets roughly 25% smaller with near-original quality — best for legal documents, portfolios, or anything headed to a printer. Medium targets about 50% smaller and is the sweet spot for everyday sharing, with no visible difference on screen. High targets about 75% smaller for tight attachment limits; text stays readable but photos may look slightly soft. The estimated size on each button is calculated from your actual file, so pick whatever fits your limit.

Tips for the best results

Scanned PDFs shrink the most. Scans are mostly images, so compression can take a 40 MB scan down to under 10 MB.
Already-small PDFs won't shrink much. If your PDF is mostly text, there's little fat to trim — that's normal, not a bug.
Need to send it? After compressing, use Merge PDF to combine related documents before sending, so the recipient gets one tidy file.

Honest limitations

Compression can't work miracles: a PDF that's already optimized, or one made of vector graphics and text, may only shrink by 5–10%. And the High setting is lossy — if you need pixel-perfect images for print, stick with Low or keep the original. Your original file is never modified; you always download a new copy.

Frequently asked questions

Is it free to compress a PDF with GroPDF?

Yes, completely free with no limits on file size or number of compressions, and no watermark added to your file.

Will compression make my PDF blurry?

On Low and Medium settings, you shouldn't notice any difference on screen or in normal printing. The High setting trades some image sharpness for maximum size reduction.

Is my file uploaded to a server?

No. Your files never leave your browser — compression happens entirely on your device, so it's safe for confidential documents.

How much smaller will my file get?

You choose: Low targets about 25% smaller, Medium about 50%, and High about 75%. After you upload, each option shows its estimated output size for your specific file. Scanned or image-heavy PDFs hit these targets easily; text-only PDFs have little to trim, so the estimate will honestly show a small reduction.