Discord Emoji Resizer

Custom emoji must be at most 256 KB. Because Discord renders them at 32x32 in messages and 48x48 in the picker, the useful upload size is 128x128 - large enough that the picker looks crisp, small enough that the file comfortably fits.

Resizing is usually enough on its own for static images. A 128x128 PNG with a modest palette lands well under 100 KB, leaving room to spare. If it does not, reducing colour depth generally saves more than compressing further at full depth.

Animated emoji are the hard case, because the limit applies to the whole GIF. Halving the frame count is the single most effective reduction, followed by trimming the palette. Reducing dimensions helps least, since a GIF's size is dominated by frame data rather than resolution.

Discord fits emoji into a square slot without stretching, so a wide image is letterboxed with empty space above and below and appears smaller than a square one. Cropping to square before uploading uses the full slot.

Transparency is preserved in both PNG and GIF, and it matters more than it seems: Discord users are split between light and dark themes, and a flattened white background that looks invisible on light theme becomes a bright rectangle on dark.

When you upload a large non-square image, Discord squashes it and resamples. Resizing to a square first avoids distortion.