RedGIFs Isn't GIF: What You Actually Download
The name is a leftover. Nothing you download from RedGIFs is a GIF file — every clip is served as MP4 video, and knowing that explains most of the questions people ask about file size and quality.
What a GIF actually is
GIF stores each pixel as an index into a palette, and that palette holds at most 256 colours. MDN's Image file type and format guide puts it plainly: “Each pixel in a GIF is represented by a single 8-bit value serving as an index into a palette of 24-bit colors.” It compresses losslessly with LZW, which is excellent for flat graphics and poor for photographic video.
That is not a small limitation. A camera clip has far more than 256 distinct colours in a single frame, so converting one to GIF means throwing most of them away and dithering the rest. The same guide recommends against it: “Prefer PNG for lossless and indexed still images, and consider WebP, AVIF or APNG for animation sequences.”
What you get instead
RedGIFs stores each post as MP4. Most have two versions — a full-size one and a smaller one meant for phones — and some carry a third with the audio track removed. MP4 is a container rather than a format: MDN's Media container formats guide lists the video codecs it can hold (AVC, AV1, VP9) separately from the audio ones (AAC, FLAC, MP3, Opus), which is why the picture and the sound can differ from file to file.
Why this matters when you choose a tool
Any tool offering to hand you a .gif is not fetching one, because none exists. It is re-encoding the video after downloading it, and you pay twice: the picture gets worse, and the file usually gets larger, because lossless 256-colour compression is a bad fit for footage that modern codecs handle well.
If what you want is the file the creator uploaded, take the MP4 and leave it alone. If you genuinely need a looping GIF for somewhere that will not accept video, convert it yourself afterwards, where you can see what the conversion cost you.
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