Compress Scanned PDF Documents
Reduce the file size of scanned receipts, contracts, and forms by 50-70% — without losing readability, without uploading sensitive scans to a server.
The Scenario
Scanned documents are the largest PDFs most people encounter. A single page scanned at 300 DPI produces a 1-3 MB file. A 20-page scanned contract can be 30-60 MB — too large for email, slow to open, and expensive to store. These are also among the most sensitive documents: scanned IDs, signed contracts, medical records, tax returns.
Why Privacy Matters Here
Scanned PDFs contain embedded raster images at high resolution. Each page is essentially a photograph of the original document. This makes them 10-50x larger than equivalent text-based PDFs. Compressing them on a server means uploading megabytes of your most personal documents — scans of your passport, tax returns, or medical records.
How to Do It
Upload scanned PDF
Drop your scanned document into the compress tool. Large files (20+ MB) may take a moment to load into browser memory.
Compress
The tool identifies and removes duplicate embedded objects, strips EXIF metadata from scanned images, and optimizes the PDF structure. Expect 50-70% reduction for typical scans.
Verify readability
Open the compressed file and check that text is still readable at normal zoom. Browser-based compression preserves the original image quality — no re-encoding occurs.
Tips
- ▸If you are scanning documents specifically for digital storage, scan at 200 DPI instead of 300 DPI — the resulting PDF will be 50% smaller at scan time.
- ▸Batch your scans: merge all pages first, then compress the single merged file. Compression is more effective on larger files because there are more opportunities to deduplicate shared resources.
- ▸Color scans compress more than grayscale. If the original is a black-and-white document, scanning in grayscale mode produces a smaller starting file.
- ▸For receipts that you need to keep for tax purposes, compress and store — the IRS accepts digital records as long as they are legible.
Why Browser-Based Processing Matters
Scanned documents are inherently personal — they are images of physical papers you chose to digitize. Passport scans, signed contracts, medical forms, tax returns. Browser-based compression ensures these images never pass through any network connection.
Frequently Asked Questions
Why do scanned PDFs compress so much more than regular PDFs?▼
Scanned PDFs contain large embedded images (one per page). These images often have redundant color data, duplicate ICC profiles, and unoptimized encoding. Removing this redundancy yields large savings. Text-based PDFs are already compact because text consumes very little space.
Will compression make scanned text harder to read?▼
No. Browser-based compression does not re-encode the embedded images. It removes structural overhead around them. The pixel data in your scans is untouched.
Can I compress a scanned PDF that has been OCR-processed?▼
Yes. OCR adds a transparent text layer over the scanned images. Compression preserves both the image layer and the OCR text layer. Search functionality is maintained.