Resize Image

No. The pica library performs the resize directly on your device, reading each photo into the browser's memory and writing the scaled result back out. Nothing about the image travels over the network at any point.

Downscaling stays sharp because pica uses a high-quality resampling algorithm, similar to what dedicated photo editors use, rather than a basic nearest-neighbor shrink. Fine details like text and edges hold up noticeably better than with a quick canvas-only resize.

Yes — a JPG stays a JPG, a PNG stays a PNG, and a WebP stays a WebP, so the resized file keeps working anywhere the original did. Only in the rare case where the browser can't re-encode the original type does the tool fall back to PNG.

Yes — choose 'Custom width' and enter a value larger than the original. Keep in mind that upscaling stretches existing pixels rather than adding real detail, so heavy enlargement can look soft or blurry, especially past double the original size.

The percentage options (25%, 50%, 75%) scale every image relative to its own original size, so a 4000px photo and a 400px photo end up at different final widths from the same percentage. 'Custom width' instead sets one exact pixel width for every image in the batch, which is useful when a form or template needs a specific size.

If you used a percentage mode, that's expected — each photo scales relative to its own starting size, so a batch of differently sized originals produces differently sized results. Switch to 'Custom width' if you need every output to share the exact same width.

Shrinking loses a small amount of fine detail, as any downscale does, but pica's resampling keeps that loss minimal and avoids the jagged edges a simpler resize can introduce. Enlarging loses more noticeably, since new pixels are estimated rather than captured, so it works best for modest size increases.