App Icon Resizer

Apple’s own guidance is to design at 1024×1024 px and scale down, because every smaller iOS size is a clean division of that master. Starting from the largest size guarantees maximum detail is available for the downscaler, and it keeps your icon pipeline single-source: redesign once, regenerate everything, and no orphaned old-version icon survives in a forgotten slot of your asset catalog.

Downscaling is not entirely mechanical, though. Fine strokes, small text, and subtle gradients that look great at 1024 px can turn to mush at 40 px. Use the generated grid as a review surface: if the smallest sizes lose their shape, simplify the master — fewer elements, thicker strokes, stronger silhouette — rather than trying to hand-tune each size separately.

This tool resizes with the browser’s canvas using high-quality image smoothing, which applies proper resampling rather than nearest-neighbor decimation. For photographic or gradient-heavy icons the output is visually indistinguishable from desktop export tools. For icons with pixel-perfect 1 px grid lines, no automatic downscaler is perfect — those designs need per-size manual adjustment regardless of the tool.

Because processing happens locally, the tool works offline once loaded and there is no file-size upload limit beyond your browser’s memory. PNGs are generated losslessly at each target dimension, so you can commit them straight to your repository without a second compression pass — though running them through an optimizer like pngcrush before release never hurts.