Getting started with Image Resizer
Resize images by size or percent, locally. A practical guide to Image Resizer: when it fits, how to get a reliable result, and the mistakes worth avoiding.
Image Resizer is worth a bookmark if the job comes up more than once. Resize images by size or percent, locally. Below: the situations where it fits, a short workflow that avoids rework, and the mistakes that most often produce a confusing result.
When Image Resizer is the right tool
Image chores are a short pipeline, and each tool here handles one stage of it well.
- Fit screenshots into documentation widths.
- Create thumbnails for galleries.
- Downscale camera photos for the web.
- Prepare app icons at target sizes.
Getting a reliable result
Crop before resizing and resize before compressing, so the encoder only works on pixels you intend to ship. Keep a lossless master and export delivery copies from it, since repeatedly re-saving a lossy file compounds the damage.
- Downscale from high-quality originals.
- Prefer WebP/JPEG for photos, PNG for UI.
- Keep aspect ratio unless you intend to crop.
Mistakes that waste time
- Upscaling tiny images and expecting sharpness.
- Disabling aspect lock and distorting photos.
- Ignoring megapixel errors on huge panoramas.
- Assuming GIF animation survives resize.
Privacy and local processing
Images are decoded and processed in your browser with Canvas APIs, and published size limits protect low-memory devices. Files are never uploaded.
Related tools and reading
Open Image Resizer to try it with your own input. Nearby utilities include QR Code Generator and SVG Viewer. For background, read Image optimisation for the web, and browse the Image Toolkit collection for the rest of the cluster.
Try related tools
Keep exploring
- learnImage optimisation for the webChoosing a format, sizing for the layout, and compressing without visible damage—an order of operations that saves the most bytes.
- learnQR Code Generator: a practical guideCreate PNG/SVG QR codes locally—no API. A practical guide to QR Code Generator: when it fits, how to get a reliable result, and the mistakes worth avoiding.
- learnSVG Viewer: a practical guideSanitize, preview, and clean SVG locally. A practical guide to SVG Viewer: when it fits, how to get a reliable result, and the mistakes worth avoiding.
- compareResizing vs Cropping ImagesScaling the whole image versus cutting a region—compare which operation preserves composition and which saves bytes.