My screen recording converted perfectly but my phone video will not.

Screen recordings are H.264; iPhone camera video is HEVC, which browsers cannot decode. Re-export the phone clip as H.264.

Best settings for a UI demo?

8–10 fps, the width you actually recorded at, and 128 colours. Interface graphics quantise very well and the result is small.

It says my video cannot be decoded.

It is almost certainly HEVC, which iPhones record by default and which no browser decodes outside Safari on Apple hardware. Re-export it as H.264, or set Settings → Camera → Formats to “Most Compatible” before recording. Extracting the audio from the same file still works, because that never touches the video track.

Is my video uploaded?

No. The decoding and the GIF encoding both happen in this tab. Video files are large, which is exactly why upload-based converters queue and cap them — none of that applies here because nothing is sent anywhere.

MOV to GIF Converter — QuickTime to Animated GIF

Turns a QuickTime MOV into an animated GIF. macOS screen recordings are MOV with H.264 video and convert straight through — which is the most common case for this page.

Screen recordings are the ideal input

A macOS screen recording (Shift-Command-5) is H.264 in a MOV, and it is close to the perfect GIF source: flat interface colours quantise to 256 with almost no visible loss, and the frame rate can drop a long way before anything looks wrong.

For a UI demo, try 8–10 fps and a width matching the region you recorded. The result is far smaller than the same clip of camera footage and looks essentially identical to the source.

iPhone recordings are the awkward case

An iPhone records HEVC by default, and no browser decodes HEVC outside Safari on Apple hardware. Such a file is refused with an explanation rather than a generic failure.

Two fixes. Change Settings → Camera → Formats to "Most Compatible", which records H.264 from then on. Or re-export the existing clip: sharing it to almost anything, or exporting from Photos at a lower quality, converts it to H.264 on the way out.

What GIF costs you

GIF is a format from 1987 and it shows in three specific ways.

256 colours per frame. Video is millions. Gradients, skies and skin tones band visibly, and nothing can prevent it — the palette is part of the format. Dithering trades that banding for noise, which sometimes looks better and always makes the file larger.

No real interframe compression. Modern video stores what changed between frames; GIF essentially stores each frame. That is why a ten-second clip becomes tens of megabytes while the source MP4 was two.

No audio. GIF has never had any and never will.

The upside is that a GIF plays inline everywhere without a play button — in an email, a README, a chat, a forum post. That is the entire reason the format survives, and it is a good one.

Keeping the file usable

Three levers, in order of effect.

Width. Halving it quarters the pixel count and roughly quarters the file. 480 pixels is plenty for most purposes and 320 is fine for chat.

Length. Every second at 12 fps is twelve more full pictures. Trim to the part that matters — the trim controls are on this page, so no separate editing step is needed.

Frame rate. 10–15 fps reads as smooth for most footage. Below 8 it starts to stutter; above 20 you are paying a lot for very little.

The practical limits worth knowing: Slack stops animating GIFs above about 2 MB, most forums cap around 5, GitHub allows 10, and Discord's free tier 10. A conversion above 15 MB is flagged in the notes.

Other names for this

Also searched as “quicktime to gif”, “screen recording to gif”.

Questions

My screen recording converted perfectly but my phone video will not.: Screen recordings are H.264; iPhone camera video is HEVC, which browsers cannot decode. Re-export the phone clip as H.264.
Best settings for a UI demo?: 8–10 fps, the width you actually recorded at, and 128 colours. Interface graphics quantise very well and the result is small.
It says my video cannot be decoded.: It is almost certainly HEVC, which iPhones record by default and which no browser decodes outside Safari on Apple hardware. Re-export it as H.264, or set Settings → Camera → Formats to “Most Compatible” before recording. Extracting the audio from the same file still works, because that never touches the video track.
Is my video uploaded?: No. The decoding and the GIF encoding both happen in this tab. Video files are large, which is exactly why upload-based converters queue and cap them — none of that applies here because nothing is sent anywhere.