How to compress a PDF for e-mail (Gmail and Outlook limits)
A brochure export, a scanned agreement or a design portfolio is often 30 to 100 MB, and the mail bounces or the recipient's server drops it quietly. The limits are lower than people think, and the fix takes a minute in the browser.
Updated 8 Oct 2026 · by the Cortex Digital Hub team
Quick answer. Gmail accepts attachments up to 25 MB per message in total; Outlook.com 20 MB; many company mail servers 10 MB. Aim for under 10 MB to be safe with any recipient. Open Compress PDF, choose a target size (the 10 MB and 5 MB pages are pre-set), drop the file, and download the result; the tool finds the lightest setting that fits and shows the final size. Text PDFs usually compress with text still selectable; scanned and image-heavy PDFs are rebuilt page by page at a lower image quality. Nothing is uploaded; it runs on your device.
Compress a PDF for e-mail → Free · opens Compress PDF to 10 MB
Step by step
- Check the size and the type: a PDF exported from Word or InDesign (text and vector) behaves differently from a scan (images).
- Open Compress PDF to 10 MB (or 5 MB for corporate recipients). Drop the file.
- For text PDFs, try Light first: it strips embedded fonts duplicates and oversized images while keeping text selectable. For scans, the pre-set target does the work.
- Download, check the size shown, attach. Over 25 MB even after compression means splitting the PDF or sending a link.
Tips that save a second attempt
- Brochures with full-bleed photos compress well: a 60 MB print PDF typically becomes 6 to 8 MB with no visible change on screen.
- Greyscale saves another 20 to 40 percent on scans and is fine for contracts and forms.
- If the recipient needs print quality, send the compressed PDF by mail and the original by a link; the mail still arrives.
- Several attachments count together towards Gmail's 25 MB. Merge them into one PDF first with Merge PDF, then compress once.
Frequently asked questions
What are the actual limits?
Gmail 25 MB, Outlook.com and Yahoo 20–25 MB, iCloud Mail 20 MB, most corporate Exchange servers 10 MB by default. Encoding adds about a third, so a 20 MB file can exceed a 25 MB limit.
Will the PDF still print well?
At 10 MB a 20-page brochure keeps print-acceptable images. For a few pages, 5 MB is plenty. Below 1 MB per 10 pages, expect visible softness in photos.
Why did Light not reduce the size?
The file is images, not text, so there is nothing to strip. Use the target-size mode, which re-encodes the page images.
Is the PDF uploaded?
No. Compression runs in your browser; the document never leaves your device.