Compress PDF
Reduce PDF file size while maintaining quality. Free, private, and instant.
How to use
- 1Drop a PDF file or click to browse.
- 2Choose a compression level, then click compress.
- 3Download smaller PDF.
How to Compress a PDF
- 1Upload your PDF file by dragging it or clicking the upload area.
- 2Choose a level, pick Low for best quality or Maximum for the smallest file, then click compress.
- 3Download your compressed PDF file.
Why Compress a PDF?
Smaller file sizes, Reduce file size for faster email uploads and easier sharing.
Maintain quality, Optimize images and remove metadata while keeping content readable.
Save storage, Compress multiple PDFs to save disk space on your device.
What compress does locally
We recompress streams: text PDFs shrink by deduplication and encoding; scanned pages re-encode images at lower quality. Text PDFs often shrink 20–60% with no visible change.
Strength by content
Text reports: compress aggressively. Scanned: choose DPI 300 DPI print-faithful; 150 DPI halves bytes but softens fine print. Keep 200–300 DPI if small text matters.
Preview
Zoom to 150–200% on smallest text. If legible, send. Close tab on shared machine bytes lived locally but in memory until you do.
Frequently Asked Questions
Savings?
Text PDFs 20–60%, scans depend on DPI.
Searchable after?
If was searchable, stays so.
Private?
Yes pdf-lib locally.
Quick Answer
Shrink a PDF locally text PDFs often drop 20-60%, scanned images depend on DPI. Private, no upload.
What is this tool?
Compress PDF makes a PDF file smaller. Text PDFs shrink a lot by recompressing streams, scanned image PDFs shrink when you lower DPI from 300 to 150. You need this for email limits or fast upload. Our tool recompresses locally and shows before/after size, all in your browser so private.
How it works
We use pdf-lib, pdfjs-dist, mammoth, and SheetJS locally. Files are read via FileReader into memory, parsed, and a new file is written. For PDFs we keep or reorder page dictionaries, for Word/Excel we map styles to PDF. All happens in your browser no upload with thumbnail previews where helpful. Very large files or 200+ pages may hit phone memory, so split first if needed.
How to use 4 steps
- 1Drop your file(s) onto the box.
- 2Pick pages, ranges, or options as shown.
- 3Preview thumbnails and order.
- 4Click Download and verify opens in Preview/Acrobat.
Specs & formulas
| Item | Detail |
|---|---|
| Lib | pdf-lib / pdfjs-dist / mammoth / SheetJS |
| Privacy | Local, no server |
| Pages | Thumbnails with drag |
| Size | Shown before/after |
Quick reference
3 worked examples
1. Packet
Three reports as three PDFs → one PDF to email.
Merge in order 2,1,3 → one file
2. Extract
50-page PDF, need pages 5-10.
Split range 5-10 → 6-page PDF
3. Fix scan
Pages 4-5 sideways.
Rotate 90° → readable
Mistakes to avoid
- Uploading private PDFs to cloud ours stays local, but close tab on shared device.
- Expecting perfect Word from scanned PDF needs OCR.
- Very large PDFs on phone split first.
Pro tips
- Check thumbnails after import.
- Keep original and work on copy.
- Verify exported PDF in Acrobat/Preview before sending.
When to use it
Contracts, invoices, research drafts, and class packets that need combining, splitting, cleaning, or compressing before sharing, all privately and fast.
Frequently Asked Questions
Are PDFs uploaded?
No processed with pdf-lib locally. Close tab to clear.
Will formatting survive Word?
Headings and lists mostly yes; scanned pages are images.
How much save on compress?
Text 20-60%, scans depend on DPI.
Can I reorder?
Yes drag thumbnails to new order.
Limit?
Large files may hit phone memory split first.