Compress a video for Outlook
Outlook attachment size limit: 20 MB in the app, 25 MB on Outlook.com
- Free to use
- Private
- No upload to the cloud
- No account needed
Compress a video
File
Compress
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- Frame rate
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- Bitrate
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- Expected size
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Keep this tab open while it works.
This browser can’t compress video yet. It needs WebCodecs, which recent Chrome, Edge, Safari and Firefox on a computer have. Firefox on Android doesn’t. Try another browser, or use the photo compressor.
Short answer
To compress a video for Outlook email, aim for 20 MB. Outlook.com on the web accepts attachments up to 25 MB, but the Outlook app stops at 20 MB for internet accounts, and 20 MB is the safe size when you are not sure which one applies. Drop your video above, keep the Outlook preset and download an MP4 of about 19 MB.
How to compress a video to send in Outlook
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Choose the video
Pick the MP4 or MOV you want to send, from a phone, a camera or your computer. The file stays on your device while it is compressed.
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Keep the Outlook preset
The size is already set to 20 MB, which is under the Outlook file size limit for internet accounts and also under Outlook.com’s 25 MB. The tool aims for about 19 MB, so a little room is left over.
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Compress
Press Compress video to reduce the video size for Outlook. Your browser re-encodes it as H.264 video with AAC sound. If the first pass lands over the target, the tool lowers the bitrate, then the resolution or frame rate if it has to, and runs again until the file fits.
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Attach it in Outlook
Download the MP4 and attach it to your message in Outlook on the web, in the Outlook app or on your phone. It is a normal MP4 file, so it goes out like any other attachment.
Outlook attachment limit: app, Outlook.com and work accounts
Microsoft publishes two different numbers. The Outlook.com attachment size limit is 25 MB. The Outlook 20 MB attachment limit applies in the app for internet accounts such as Outlook.com and Gmail, and it counts the whole email, not just the file. Work and school accounts start lower. If you are not sure which one applies, use the smaller figure. All the email attachment size limits are on one page.
| Where you send from | Limit | What counts |
|---|---|---|
| Outlook.com on the web | 25 MB | File attachments |
| Outlook app, internet accounts (Outlook.com, Gmail) | 20 MB | The Outlook email size limit covers the attachment and the email together |
| Outlook app, Exchange work account | 10 MB (default) | The whole email, so the file itself can only be about 7 MB. Your organization may use another figure |
Sources: Microsoft: attachment size in Outlook and Microsoft: Outlook.com sending limits, checked 8 October 2026. Limits change, so the date shows when we last checked.
Questions about Outlook and video
How to send a large video through Outlook?
Make a smaller copy first. Choose your video above, keep the Outlook preset and download the result. It comes out at about 19 MB, so it fits the app’s 20 MB limit and Outlook.com’s 25 MB. If a video is too long to fit at all, the tool tells you instead of giving you a file that will not go.
How big of a file can you send through Outlook?
It depends on where you send from. Outlook.com on the web accepts file attachments up to 25 MB. The Outlook app allows 20 MB for internet accounts, and an Exchange work account starts at 10 MB by default. For work email, compress video to 10 MB.
Is the Outlook app attachment size limit different from Outlook.com?
Yes. Microsoft gives 25 MB for attachments on Outlook.com and 20 MB for the Outlook app when it uses an internet account, including an Outlook.com or Gmail address. Because the same address can be opened in either place, 20 MB is the number to plan around.
Why is my Outlook attachment too large?
The limit applies to more than the file. Microsoft says the 20 MB limit includes both the size of the attachment and the size of the email, so your text and any other files count too. A video that is right at 20 MB leaves no room, which is why the tool aims for 19 MB.
What is the Outlook email video size limit, and does Outlook compress videos?
Microsoft publishes one attachment limit and no separate one for video, so a video counts like any other file. Its help page says nothing about Outlook shrinking videos for you, so plan on the video going out at its own size. At the 20 MB size, good quality holds about 33 seconds at 1080p, 1 minute 12 seconds at 720p or 2 minutes 34 seconds at 480p. The video size calculator shows what fits for any length.
Is the Hotmail attachment size limit the same?
Microsoft says Hotmail.com was rebranded as Outlook.com and signs in to the same account, so a Hotmail address is an Outlook.com account. On the web the Outlook.com figure in the table applies. In the Outlook app, plan for 20 MB.
Is my video uploaded when I compress it?
No. Your browser does the work on your own device, and the page never receives the file, so there is no upload to wait for. It runs in current Chrome, Edge, Safari and Firefox, and on an iPhone in Safari.
Will the video look worse after compression?
A little, yes. Shrinking a video means discarding detail, and the smaller the target, the more is lost. For a short clip 20 MB is generous, while a long one is scaled down to fit. Play the result before you download it. Your original is never touched.
On iPhone
Video Compressor: Metras
Our iPhone app makes smaller copies of the videos in your library, right on the device. Choose 20 MB for Outlook or enter a size of your own, see the estimate before you start, and compare the copy with the original afterwards. Nothing is uploaded to a server, large batches run in the background with Premium, and your originals stay in Photos until you decide.
Coming soon to the App Store
