What is Image Resizer?

Resizing an image sounds trivial until you run into the wrong tool for the job. Many server-side resizers re-encode your image with aggressive compression to save their own bandwidth costs, degrading quality in ways that aren't obvious until you zoom in. This tool uses the HTML5 Canvas API to resize locally, so what you put in is what you get out — at the exact dimensions you specify. **Pixel-accurate dimensions** — Enter a target width, height, or both. Aspect ratio lock keeps proportions correct by default; disable it if you need to stretch to a non-proportional size (useful for social media headers with fixed aspect ratio requirements). **Percentage-based scaling** — Instead of calculating pixel dimensions manually, you can enter ‘50% of original’ or ‘200%’ and the tool computes the output size. Useful for batch-consistency across images that don’t share the same starting resolution. **Resampling quality** — Downscaling uses a bicubic-equivalent resampling algorithm through the Canvas API, which averages neighbouring pixels to maintain sharpness. Upscaling beyond the original resolution will introduce softness — no resampling algorithm can create detail that wasn’t captured.