Image Resizer

Are my images uploaded to a server?

No. Resizing runs entirely in your browser using a canvas — the image is never uploaded or sent anywhere, so it works offline and keeps private photos private.

Does locking the aspect ratio keep my image from stretching?

Yes. With Lock aspect enabled, changing the width updates the height automatically (and vice versa) so the image keeps its original proportions and never looks squashed or stretched.

Which output format should I choose?

PNG keeps transparency and is lossless; JPEG and WebP are smaller and let you set a quality level. For photos pick JPEG or WebP, and for graphics with transparency or sharp edges pick PNG.

Will resizing make a small image look sharp at a larger size?

Enlarging beyond the original dimensions cannot add detail that was not there, but the high-quality Lanczos resampling keeps upscaled and downscaled results as smooth as possible.