- Why is the MP4 so much smaller than the GIF?
- GIF compression works on one frame at a time and can only see runs of repeated pixels, so an animation that barely changes still stores most of each frame again. H.264, the video codec inside the MP4, stores what changed between frames and compresses color far better, without GIF's 256-color limit. Screen recordings, movie clips, and reaction GIFs often shrink to a tenth of their size or less. Small, flat pixel-art GIFs are already efficient, so they shrink less — a very tiny GIF can even come out a little bigger. The tool shows the real before-and-after once it's done, so you don't have to guess.
- Is my GIF uploaded anywhere?
- No. The GIF is read and decoded by code running in your browser tab, each frame is drawn onto a canvas, and your browser's built-in video encoder writes the MP4. Nothing is sent to a server, so there's no upload wait and no copy of your file left on someone else's computer. You can open your browser's network tab while it converts and see for yourself.
- Will the video play at the same speed as the GIF?
- Yes, and that's harder than it sounds. Every GIF frame carries its own delay in hundredths of a second, and the MP4 keeps each one, so a GIF that pauses on a punchline still pauses. There's one quirk worth knowing: many GIFs store a delay of 0 or 1 hundredth of a second, and Chrome, Edge, and Firefox play those frames at a tenth of a second instead. The converter does the same, so the video matches what you saw in the browser rather than turning into a one-second blur.
- What happens to transparent parts of the GIF?
- MP4 video can't store transparency, so transparent pixels are filled with white — the way the GIF looks on most web pages and in light-mode chat apps. Frames that only update part of the picture are rebuilt in full first, so leftover or half-cleared areas don't show up as glitches in the video. If you need a transparent animation, keep the GIF, or use a format like WebM or animated PNG that supports it.
- Why does the MP4 stop instead of looping?
- A GIF carries a loop setting; an MP4 file doesn't. Most video players play it once and stop, although Instagram, X, TikTok, and many messaging apps loop short videos on their own. If your GIF is only a second or two, pick 2×, 3×, or 5× before converting — the animation is repeated inside the video so it lasts long enough to register, and the total length is shown before you click Convert.
- Does the video keep my GIF's size?
- Usually exactly. The one change is that H.264 needs even numbers for width and height, so a 499 × 281 GIF becomes a 498 × 280 video. GIFs bigger than 1080p are scaled down to fit 1920 × 1080, the size every phone and social site plays smoothly. GIFs whose shorter side is under 128 pixels — emoji, sprites, pixel art — are scaled up by a whole number, like 4×, with sharp pixels instead of blur, because some players refuse to open videos that tiny.
- What are the limits?
- GIFs up to 200 MB, up to 20,000 frames, and a canvas up to 4096 × 4096 pixels (16.7 million pixels, the largest image an iPhone browser can draw). The finished video can be up to 10 minutes long, including repeats. Those limits keep the conversion reliable on phones and older laptops; anything past them is better trimmed in an editor first.
- It says my browser can't make MP4 video. What now?
- Encoding H.264 in a web page relies on a browser feature called WebCodecs. Current versions of Chrome, Edge, and Safari have it, and so does Firefox on computers. Update your browser and try again, or switch to one of those. The MP4 has no sound track either way, since GIFs never contain audio.
