Compress PDF
Reduce PDF file size while keeping text and images clear. Upload once and download a smaller file.
Fit-or-split result: get one PDF that fits, or a ZIP of parts under the limit.
Email presets: Gmail 25MB, Outlook 20MB, Outlook.com 25MB, plus custom size.
Private by default: files auto-delete after 60 hours; we don't store document contents in logs.
How it works
Upload
Pick a PDF and a target limit.
Process
We optimize and split as needed.
Share
Download a single file or parts.
Compression FAQ
Will compression reduce quality?
You can keep a balanced look or pick a higher quality preset in the email-ready workflow.
Can I target a specific size?
Yes. Pick Gmail 25MB, Outlook 20MB, or set a custom MB target.
Why compress PDFs with PDFThin
Built for busy workflows
Send, upload, or archive PDFs with predictable results.
Ideal for scanned documents and large reports.
Email and organization workflows
Need strict attachment limits? Start with the email-ready workflow and choose a preset.
For oversized files, split by size keeps each part under the limit. To clean up pages, use Organize PDF pages. For scan-heavy files, see reduce scanned PDF size.
Related tools
All PDF tools
Browse every PDFThin tool in one place.
Email-ready compression
Shrink PDFs to Gmail/Outlook limits with quality control.
Split by size
Split large PDFs into size-safe parts.
Organize PDF
Merge, rotate, delete, reorder, and split pages.
Popular guides
All PDF guides
Browse every step-by-step PDF guide.
Compress PDF for email (complete)
Step-by-step workflow for Gmail 25MB and Outlook 20MB limits.
Reduce scanned PDF size
Keep text readable while shrinking scanned documents.
Split PDF by size
Create parts that stay under a target MB limit.
Rotate PDF pages online
Fix page orientation for sideways scans or photos.