Support

How do I compress a video?

Pick a video, then pick where it is going — Email, Discord, WhatsApp, or a size you type in yourself. Slimsend works out the resolution and bitrate that land under that ceiling and does the rest. There is no resolution dropdown to guess at; that guess is the app’s job, not yours.

Which size limits does Slimsend know about?

Email is 25 MB, Discord is 20 MB and WhatsApp is 64 MB. You can also type any size in megabytes, or ask for a copy that is simply smaller than the one you have. These are the published free-tier limits at the time of writing — if a service changes its limit, use the custom size.

My file came out just over the limit somewhere else. Why not here?

Because a 25 MB limit means 25,000,000 bytes, not 26,214,400. Aiming at the second number — which is what "25 MB" means to a lot of software — puts the file about 5% over, and the send fails. Slimsend works in decimal bytes from end to end, so under the limit means under the limit.

Slimsend warned me the result would look bad. Is that a bug?

No, it is arithmetic, and it is the point. A ten-minute video inside a 25 MB email is 360p no matter which app you use. Most apps let you find that out afterwards. Slimsend tells you before the encode and offers the alternative: trim to a length that fits at a higher resolution, or carry on at 360p. Your call, made in advance.

Slimsend refused to compress my video. Why?

There are three refusals, and each one exists to stop you wasting quality for nothing:

• Already under the limit — there is nothing to gain, so it says so instead of re-encoding your video for no reason.
• Too close to the limit — re-encoding would cost quality and could even make the file bigger.
• Impossible — when the audio alone is over the limit. Slimsend tells you the smallest the file can be, so you know what you are actually up against.

Does Slimsend upload my video?

No, and it could not if it wanted to. The app makes no network requests at all — there is no server, no account and no queue. It works in Airplane Mode. See our Privacy Policy for the details.

Does it delete or change my original?

Never. The compressed video is written as a new file; your original is left byte-for-byte as it was. It is still worth checking the compressed copy plays before you delete anything — that is good practice with any compressor, ours included.

Where does the compressed video go?

When you save, it is added to your photo library in a Slimsend album, keeping the original recording date and location so it sits in the right place in your timeline. You can also share the file straight to another app without saving it at all.

Is Slimsend really free?

Yes. No ads, no subscription, no in-app purchase, no watermark, no account. It does not gate the export, the resolution or the number of videos you compress.

Do I need an internet connection?

No. Every step runs on your iPhone, so Slimsend works offline and in Airplane Mode.