How to make a video small enough to send

Video from a phone is big, and most email services refuse a message somewhere around twenty or twenty five megabytes. There are two honest ways out: make the video smaller, or stop attaching it. This guide does both, with the numbers worked out so you know which one you need before you start.

How small does my video need to be?

Video size is simple arithmetic: size = bitrate × duration. A file has a budget of bits, and the longer the video, the fewer of them each second gets. Email makes it tighter, because an attachment is encoded as text on the way, which turns every three bytes into four. A 25 MB limit leaves room for a file of about 18.75 MB.

Put in the length of your video and the limit you are up against. The first numbers are pure arithmetic. The table underneath is not: each row is a real re-encode of a one minute test clip with a setting you can pick in Nemi, measured, and scaled to your length.

Which settings make a video smaller?

Three things decide the size of a video, and Nemi's converter lets you change all three.

• Size in pixels. Fewer pixels, fewer bits. A 1280 pixel wide video has less than half the pixels of a 1920 wide one, and on a phone or in an email preview nobody can tell.
• Quality (CRF). A number from 0 to 51 that tells the encoder how much detail it may throw away. 23 is the default. Higher is smaller and softer, and how much smaller depends on the footage, as the chart below shows.
• Video bitrate. Instead of a quality, a target: 1, 2.5, 5 or 10 Mbps. Use it when you must hit a size, because the encoder aims at that average whatever the picture looks like.

On this clip, leaving everything alone gave 36 MB for the minute. Raising the quality number to 28 brought it to 14 MB, and doing that at 1280 wide gave 7.1 MB. Each step also lowered the match with the source, which is the trade you are making: the clip has a fine grain over it, like most footage from a small sensor, and a higher quality number smooths that away first. On a phone screen it is hard to see; on a television it is not.

How do I make a video smaller in Nemi?

Not with the Compress button, which is the first place people look. Compress packs files into a ZIP or a TAR, and an MP4 is already compressed: zipping it saves almost nothing. Making a video smaller means re-encoding it, and in Nemi that is Convert.

1. 1

   Upload the video and press Convert

   Select it in your files and press Convert in the toolbar, or right-click it.
2. 2

   Pick MP4

   Under Convert to, choose MP4. If the video already is an MP4, it is offered anyway: converting a file to its own format re-encodes it with your settings. MP4 plays everywhere, which matters more for an attachment than anything else.
3. 3

   Open the MP4 settings

   Under Settings, open MP4. Type a width under Size in pixels, such as 1280, and leave the height empty so it keeps its shape. Then either raise Quality (CRF) to around 28, or pick a Video bitrate from the calculator above. Use one of the two, not both. Anything you leave alone keeps its default.
4. 4

   Download it, or keep it next to the original

   Under Result, Download sends the smaller file straight to your device, ready to attach. Save to workspace puts it next to the original, which is never replaced.
5. 5

   Press Convert

   A video costs 5 units of your daily allowance. The panel shows its progress through the file, and you can cancel at any point without spending anything.

Should I send a link instead?

Often, yes. Squeezing a five minute video under 25 MB leaves well under a megabit a second for the picture, and the calculator will show you what that means. If the person on the other end needs to see the video properly, shrinking it to fit an inbox is solving the wrong problem.

A share link sends the file itself, at full quality, as a link in the email. It does not count against anybody's attachment limit, the recipient can watch it in the browser before downloading, and you can put a password and an expiry date on it. The largest single file you can share is 0.5 GB on Free, 5 GB on Starter, 15 GB on Creator, 25 GB on Pro, 100 GB on Max and 200 GB on Business.

• Shrink it when it has to be an attachment: a form that only takes files, a recipient who never clicks links, or a clip that is short to begin with.
• Send a link for everything else, and always when quality matters: a client review, a wedding film, footage somebody will edit.

Our guide to sending large files securely covers the link side in depth, and every format Nemi converts is in one searchable list.