Compress video for Outlook
Fit a video under the 20 MB limit of the Outlook desktop app, which also works for Outlook.com.
Drop a video, or choose a file
MP4, MOV, WebM or MKV. Any size.
Your file never leaves your device
Email limits
| What | Official limit | Source |
|---|---|---|
| Outlook.com | 25 MB per file | support.microsoft.com |
| Outlook desktop app | 20 MB total for Outlook.com, Gmail and other internet accounts | learn.microsoft.com |
| Microsoft 365 work accounts | 35 MB per message by defaultYour admin can change it. Includes about 33% encoding overhead. | learn.microsoft.com |
Limits verified Oct 2, 2026 against official sources.
Report an outdated limitWhy files fail on Email
The Outlook desktop app limits Outlook.com, Gmail and other internet accounts to 20 MB (20480 KB) in total, less than Outlook.com allows on the web. Work accounts follow whatever limit your admin set.
What this preset does
This preset compresses to just under 20 MB with room for the message, so it sends from the Outlook app, the web and phones.
Questions
- Why does Outlook say the attachment exceeds the allowable limit?
- The desktop app's default limit for internet accounts is 20 MB, even though Outlook.com on the web allows 25 MB.
- What about work or school accounts?
- Microsoft 365 defaults to 35 MB per message including encoding overhead, but admins can change it.
- Can I share bigger files from Outlook?
- Yes, by attaching a OneDrive link instead of the file itself.