Image Resize

Image Resize changes a photo's pixel dimensions — its width and height in pixels — right in your browser. It's the fix for one specific, common problem: an upload rejected for being "too large" when the file itself is small. Nothing is uploaded; the resize runs on your device using the browser's built-in image APIs.

The trick: leave one side at 0

You don't set both dimensions. Enter the width or the height and leave the other field at 0, and the tool computes the missing side from the image's original aspect ratio. Ask for 800px wide and it works out the matching height so the picture keeps its exact proportions — nothing comes out stretched tall or squashed flat. That single behavior is what separates this from a naïve resize where you type both numbers and accidentally distort the image.

• Width 800, height 0 → 800px wide at the correct proportional height.
• Width 0, height 600 → 600px tall, width computed.
• Fill in both → you're deliberately overriding the aspect-ratio lock.

Pixel dimensions vs. file size — not the same thing

This is the misunderstanding behind most "image too large" errors. A form that says max 2000px wide is checking pixel dimensions, and it will reject a 4000px-wide photo even if the file is only 50KB. A form that says max 500KB is checking file size in bytes. Resizing down fixes the first, and it usually shrinks the file too (fewer pixels means less data) — but if you're chasing a specific KB budget, resize first and then run the result through Image Compressor, which controls quality and format directly.

Shrinking is safe; enlarging isn't

Making an image smaller is close to lossless — you're discarding detail you no longer need, and the result stays sharp. Making it bigger is a different operation: the tool has to invent pixels that were never captured, interpolating between the ones you have, which is why an enlarged photo looks soft or blurry along its edges. No setting avoids this; it's a consequence of the detail simply not existing in the source. The rule: always start from the highest-resolution original you have and scale down. Treat upscaling as a last resort, and expect softness when you do it.

Chaining it with other steps

Resize is often step one in a pipeline. Add it to a Spell Chain (Flow) followed by Image Compressor to satisfy both a pixel limit and a file-size limit in one pass, or followed by Image Converter to change format at the same time — for example, resize a camera JPG to 1200px and convert it to WebP for the web without ever saving an intermediate file.

No size ceiling, but memory matters

Because everything happens locally, there's no server-imposed limit on how big an image you can load. The real constraint is your device's memory: a very large image (tens of megapixels) may take a moment to process on an older phone, while typical photos resize instantly.