Compress PDFs online: scans and image-heavy files often shrink substantially (depends on quality settings). Local processing, no upload.
TL;DR: Free PDF compressor: scanned PDFs often shrink substantially (depends on quality settings), processed locally for upload limits.
For local tools, open DevTools → Network and search your input — it should not appear in requests.
Usage Guide
Oversized scanned PDFs hit email and portal limits. Rasterize pages at adjustable quality and rebuild locally — great for image-heavy files; vector text PDFs may grow.
1. Compress
Pages render to JPEG then re-embed — gains come from smaller rasters.
- Drop a PDF.
- Pick quality and run.
- Compare sizes and download.
2. Identify the PDF
Scans shrink; tiny vector text may grow. If size rises, split/delete pages or rescan at lower DPI instead.
3. Quality
Legal archival may forbid lossy compression.
- Proof on screen and in print.
- Watch small type and stamps.
- Sample one page first.
4. Failures
No upload; work stays in the browser session.
- Encrypted PDFs need unlock elsewhere.
- Reject corrupt inputs.
- Large page counts take time.
5. With split/merge
Compress only the heavy scanned appendix, then merge back.
6. Checklist
Treat the compressed file as a delivery copy.
- Spot-check readability.
- Confirm page count.
- Keep the master until receipt is confirmed.
7. Acceptance after compress
Spot-check searchability, image sharpness, and page count. Work stays local; very large files may hit browser memory limits. Use sibling PDF tools for reorder/merge — compress does not redesign layout.
FAQ
Text-only vector PDFs are already tiny, and rasterizing pages into images grows them — that is this tool's boundary, and the UI reports the before/after sizes honestly. Scans and image-heavy files see the big wins (typically 60–90%). If the size climbs instead, switch to deleting pages, splitting, or lowering scan DPI at the source rather than grinding quality down.
Yes. Each page is re-rendered as an adjustable-quality JPEG, so text edges soften slightly; 50–65% quality is usually imperceptible on scans. Stamps, handwritten notes, and small type degrade first — compress a one-page sample before committing to the whole file.
No. Pages become images, so text turns into pixels — searchable archives need an OCR-equipped pipeline. Treat the source as the master and the compressed file as the delivery copy, and keep the original until the recipient confirms receipt.
Split those heavy pages out with the PDF splitter, compress them alone, then merge back, so the lean text pages are not rasterized along for the ride. The reverse case — merged scans ballooning in size — is another classic job for this tool.
Encrypted files cannot be processed without the password; corrupted files or extension/content mismatches fail outright. Very large page counts run slowly — let the progress finish instead of stacking tasks with repeated clicks.
It doesn't. Rasterizing and repacking happen within the current browser session — progress and results never leave your machine.
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