Best Image Size for Email Attachments (14MB, 10MB, 5MB Limits)
Best Image Size for Email Attachments (Limits + How to Fit)
You don't know a photo was too big for email until the send button fails. Here are the real attachment limits for major providers, the exact sizes that fit, and a 30-second fix using free online tools.
Email attachment limits (2026)
- Gmail: 25MB
- Outlook / Microsoft 365: 20MB
- Yahoo Mail: 25MB
- iCloud Mail: 20MB
- Zoho Mail: 20MB
- QQ / 163 Mail: 5-8MB (typical Chinese providers)
- Many corporate servers: 10MB
A single phone photo is 3-12MB. Two photos plus a signature can already exceed corporate limits.
The sizes that always work
- Inline email image: 600-800px wide
- Photographic attachment: 1200-1600px wide, under 500KB
- Thumbnail / preview: 200-300px wide
- Newsletter header: 600×400px
Rule of thumb: if your image is over 1MB, resize it before emailing.
How to fit any image in 30 seconds
- Resize first — open the Resize Image tool, set width to 1200px, download.
- Compress second — drop it in the Compress Image tool, set quality to 75%, watch the live size drop below 500KB.
That's it — two steps, browser only, nothing uploaded. The compress for email guide covers JPG-specific notes, and resizing for email has the dimension table.
What about PDF attachments?
If you're sending several photos, they fit as one file when merged into a PDF — single attachment, no 20MB wall. Use Merge Images to PDF.
Remember: 1200px wide + 75% quality ≈ 200-500KB ≈ fits every limit above. Keep the original on your drive, send the small copy.