Video to GIF

Drop the file in, set the start and end seconds, pick a frame rate and a width, and press Start. Nothing is uploaded, there is no sign-up, no watermark is added and there is no cap on how many you convert. If the result is bigger than you want, change one of the three settings and run it again.

GIF dates from 1989 and has no lossy compression and no motion compensation. Every frame is stored as indexed pixels and squeezed with LZW. Ten seconds at 480 pixels wide and 12 frames a second usually lands somewhere between 2 and 6 MB; the same ten seconds as MP4 is often under 500 KB. Seconds, frame rate and width each multiply the total, so a minute at full width runs into hundreds of megabytes, and your browser will normally run out of memory before it finishes.

256 colours per frame is the ceiling of the format, not a setting. Anything smooth, such as a sky, a shadow or the noise that video compression leaves behind, cannot be written as it is, so it is dithered: scattered dots of two colours that your eye reads as a third. Flat graphics, slides and screen recordings come out clean; filmed footage with gradients in it will show the dithering if you look. That is the format, not the tool.

GIF stores each frame delay in hundredths of a second, so only some rates come out exactly. 10, 20 and 25 are exact. 12 is written as 8 hundredths and plays at 12.5. 15 is written as 7 and plays at about 14.3. File size is close to linear in frame rate, so halving it roughly halves the bytes, and below about 8 frames a second most motion starts to read as a slideshow.

No. The format has no audio track of any kind. Whatever sound is in the source is dropped. If the sound matters, the clip needs to stay a video.

Yes, forever. The loop block that browsers read is written into every file this page produces.

There is no length written into the page; the limit is the machine you are on. The decoded frames and the finished GIF both sit in this tab while it works, so a long clip at a high frame rate and full width is what runs out of memory first. If that happens you get a message saying so and the page stays up; try a shorter stretch, a lower frame rate or a narrower width. The size of the file barely matters, because only the seconds you asked for are read: we took ten seconds out of a 2.2 GB recording here in 1.7 seconds. That only holds for MP4; other formats go through the video engine, which cannot read past about 2 GB in one piece.

It is not. The file is read inside this tab and the GIF is built inside this tab: by the browser's own decoder for an MP4, or by an engine downloaded from this site for other formats. You can watch the network panel while it works.