Compress Video for Outlook Email Attachments
Choose a smaller video for an Outlook attachment. The 20MB target is a starting point, not a guarantee of delivery. Check both mailboxes and lower it when message overhead or organization policies require more room.
Quick answer
Outlook.com and Outlook client guidance describe different limits. Verify your product and account first, choose a target below the applicable limit, and review the downloaded MP4 before attaching it yourself. VidSlim does not connect to your mailbox, upload the video, or send email.
How to compress a video for Outlook
- Check the sender and recipient mailbox limits and organization policies.
- Choose a local video and a target below the applicable limit. The 20MB preset is only a starting point.
- Compress and review the downloaded MP4, then attach it in Outlook yourself or use an approved sharing link.
Tips for a better result
- Limits may cover the whole message, including other attachments and overhead—not just the video.
- Use an approved sharing workflow for a long clip when lowering the target makes important details unclear.
Reviewed 2026-09-17
Which Outlook size limit applies?
Outlook.com attachment help lists 25MB for the whole message. Microsoft's separate Outlook client guidance lists 20MB for internet mail and a 10MB default for Exchange, including the email and attachments. Managed accounts can differ. Neither 20MB nor 25MB guarantees delivery; verify your product and both mailbox policies.
Sources: Outlook.com attachment help · Outlook client size guidance · Reviewed 2026-09-17
Frequently asked questions
- How do I compress a video for an Outlook email?
- Check the applicable limit, choose the video and a target below it, then compress and inspect the downloaded file. Leave room for the rest of the message; 20MB is not a guaranteed safe size.
- What is Outlook's attachment size limit?
- Outlook.com help lists 25MB for the whole message, while separate Outlook client guidance lists 20MB internet-mail and 10MB default Exchange limits. Check the product, account and organization rather than assuming one universal ceiling.
Related private video workflow
Need the broader decision tree? Read the guide on compressing video without uploading it. If you need a short silent loop instead of an MP4, try the video to GIF converter.
For mailbox limits, use Compress Video for Email. When a larger file is acceptable, try the 50MB target.
Trying to send the file as an attachment? Use the guide to send a video by email when the file is too large before deciding whether to compress further or send a cloud link.