Compress PDF
Compress PDF files free — cut the size for email or upload limits. Up to 50 MB per file, batch queue, ZIP download, and nothing ever uploaded.
Compress a PDF online free and make the file smaller for email or upload limits — up to 50 MB per file and as many files as you like in one batch. Made for anyone stuck at an attachment size cap. The PDF never leaves your device: there is no upload step at all, and you can download each result or all of them as a ZIP.
Drag & drop PDF files here
or click to browse — add multiple PDFs to compress them in a batch
PDF files only — up to 50MB each
How to compress a PDF file
Compressing a PDF rebuilds the document with object streams enabled and drops redundant objects, which trims the file's internal overhead. Text stays sharp and selectable and images keep their original quality — the trade-off is that image-heavy files have little structure left to strip, so they shrink less. Everything runs in your browser, so there is no upload wait and no server copy of your document.
Add your PDF
Drag your file onto the box above, or click to browse. Each file can be up to 50 MB, and you can queue as many as you like — each one shows its original size as soon as it is added.
Compression runs automatically
There are no settings to choose: each file is processed in turn straight away, with live per-file status. Text-heavy documents with redundant structure are the ones that shrink most.
Compare the before/after size
Every row shows the original size, the compressed size, and the percentage saved, so you can see exactly what the compression achieved before you commit to using the file.
Download one file or all of them
Download results individually, or grab every compressed PDF as a single ZIP. Files stay in your browser's memory and disappear when you close the tab.
Why people compress PDFs
Email attachments that keep bouncing
Most email providers cap attachments at 20-25 MB. Compressing brings scanned contracts, reports, and brochures under the limit without splitting them into several emails.
Upload forms with hard caps
Government portals, university systems, and job applications often reject anything over a few megabytes. Compressing gets your document past the check on the first try.
Faster sharing and smaller archives
Smaller files send faster over chat apps, take less room in cloud drives, and cost less to store when you are archiving hundreds of documents.
Key features
Structure-level optimization
The PDF is rebuilt with object streams enabled and redundant objects removed. Text stays selectable and images are not re-encoded, so visual quality is preserved.
Batch queue with ZIP download
Drop a stack of PDFs at once; they are processed one after another with live per-file status, then downloaded together as a single ZIP.
Before/after size for every file
Original size, compressed size, and percentage saved are shown per file, so you know what the compression actually gained instead of guessing.
Supported formats
- Input: PDF (.pdf) — one file up to 50 MB, any number of files per batch
- Output: compressed PDF (.pdf); page count, page size, and page order unchanged
- Works in any modern desktop or mobile browser — no install, no account, files stay on your device
Privacy and security
Limitations
- This is structure-level compression: images inside the PDF are not re-encoded, so image-heavy and scanned files may shrink only slightly.
- Scanned (image-only) PDFs are already image-compressed, so expect little or no size change — there is no image-quality setting here to trade for extra savings.
- Password-protected PDFs must be unlocked first (use Unlock PDF), then compressed normally.
- One file at a time is limited to 50 MB, and very large or complex documents are bound by your device's available memory rather than a server quota.
Related Tools
All tools
Merge PDF
Combine multiple PDF files into one document in the order you want.
Combining several files into one first? Merge them, then compress the single result for sending.
Split PDF
Extract pages or split a PDF into separate files in a couple of clicks.
Only part of a big file needs sending? Extract those pages first, then compress just the extract.
Frequently Asked Questions
Will compressing lower the quality of my PDF?
No. The tool rebuilds the file's internal structure and strips redundant objects — text stays crisp and selectable, and the images inside the document are not re-encoded. There is no lossy image setting on this page.
How much smaller will my PDF get?
It depends entirely on the file. PDFs with redundant structure, unused objects, or many small text streams shrink the most. Scanned or photo-heavy PDFs are dominated by already-compressed image data, so they may barely change.
Is there a file size or page limit?
Each file can be up to 50 MB. There is no page-count cap and no limit on how many files you queue; very large or complex documents are bounded by your device's available memory, since all processing is local.
Are my files uploaded to a server?
No. Compression runs locally in your browser with pdf-lib. Files are processed in memory and never leave your device — close the tab and nothing remains.
What happens if one file in a batch fails?
That file is marked as failed with a plain-language explanation, and every other file still completes. Successful files stay downloadable individually or as a ZIP, so one bad file never costs you the whole batch.