Compress a video to 25 MB

You are trying to send a video by email, where the big providers all stop at the same number. The catch is that email limits count the encoded message, so the file you can actually send is well below the number on the box. This page shows what fits at the full size, and explains why an attachment needs a smaller target.

How long a video fits in 25 MB

The longest clip that keeps each resolution at each quality, worked out with the same arithmetic FitSize uses to plan an encode. Times use h, m and s for hours, minutes and seconds, and are rounded down, so a clip at the listed length fits.

Assumes 30 fps, a 16:9 picture and stereo AAC audio at 128 kbps. A different frame rate, a taller picture or a bigger audio track changes the times.

Worked examples

• A 30-second clip: 1080p at Balanced quality (that resolution holds up to 37 s).
• A 2-minute clip: 480p at Balanced quality (that resolution holds up to 2 min 52 s).
• A 10-minute clip does not fit in 25 MB at any resolution FitSize offers. Trim it or accept a smaller target.

What quality to expect

A 2-minute 720p clip at this size gets about 0.053 bits per pixel per frame. That is below our Balanced preset (0.08) and above our Smallest (0.05), so expect softness in fast motion; a lower resolution will look better than 720p here. This is an estimate from bitrate arithmetic, not a measurement: real quality depends on the footage, and fast motion or fine detail needs more.

Who needs 25 MB

These verified limits are at or just above 25 MB. Where a limit is for email, the file has to be smaller than the number, so the third column is what to aim for.

What each of these limits covers

• GitHub: Other files (PDF, zip, and so on). The limit for all attached files that aren't images or videos. Source: docs.github.com
• Gmail: Personal account attachments. The help page gives 25 MB for personal accounts; Google Workspace administrators set their own sending and receiving limits. Over the limit, Gmail turns the attachment into a Google Drive link. The page doesn't say whether the 25 MB counts the encoded message. We assume it does, because email attachments travel base64-encoded (about 37% larger), so the file has to be well under 25 MB; FitSize aims for the smaller usable size. Source: support.google.com
• Outlook.com: Attachments. The page gives 25 MB for attached files and 2 GB for files shared from OneDrive. It states no separate limit for the whole message, and doesn't say whether the 25 MB counts the encoded message; we assume it does (see the encoding note on gmail-personal). Source: support.microsoft.com
• Proton Mail: Outgoing attachments. Total attachment size for outgoing email is 25 MB (50 MB incoming), up to 100 files. Proton notes that encoding makes attached files a bit larger than on the sender's device, so the file budget is smaller than 25 MB. Source: proton.me
• Yahoo Mail: Attachments (sent or received). The sum of all attached files in one message, incoming and outgoing, must not exceed 25 MB. The page doesn't say whether that counts the encoded message; we assume it does. Source: help.yahoo.com

Tips at 25 MB

1. For email, treat the smaller usable size on each destination page as your real target, not the number in this page's title.
2. A cloud link is the normal way past this limit for a long video. Gmail and Outlook both document one: a Drive link for Gmail and a OneDrive link for Outlook.
3. Do not compress a video you can trim. Cutting the start and end of a clip costs nothing in quality, and at this size it can be the difference between a resolution that fits and one that does not.