Image Resizer
Resize and compress images in seconds. Change the dimensions or shrink the file size of any JPG, PNG, or WebP — without distortion, and without uploading anything.
Resize an image without losing quality
The most common reason to resize an image is to fit a size limit — an upload cap, an email attachment, or a platform’s required dimensions. AspectKit lets you do it precisely: type an exact width or height, scale by a percentage, or snap to a maximum width like 1080px. With Lock ratio on, the image scales proportionally so it never looks stretched.
Reduce image file size
To make a file smaller, combine two levers: lower the dimensions and reduce the quality. Exporting as JPG or WebP at 70–85% quality typically cuts file size dramatically with no visible difference. The tool shows the new size and exact percentage saved as you adjust, so you can hit a target without guesswork.
Frequently asked questions
How do I resize an image? +
Upload your image above, then enter a new width or height (with “Lock ratio” on, the other value updates automatically so nothing stretches), or use a scale preset like 50%. Pick a format and click download. Everything runs in your browser.
How do I reduce an image’s file size? +
Two ways, both supported here: shrink the dimensions (e.g. to 1080px wide), and/or lower the quality slider and export as JPG or WebP. The tool shows your new file size and the percentage reduction in real time.
Will resizing distort my image? +
Not if you keep “Lock ratio” enabled — width and height scale together so the proportions stay identical. Turn it off only if you intentionally want to stretch to specific dimensions.
Is my image uploaded to a server? +
No. AspectKit resizes images entirely in your browser using the HTML canvas. Your photos never leave your device and are never uploaded or stored.
What image formats can I use? +
You can open JPG, PNG, and WebP images, and export to JPG (smallest), WebP (modern and small), or PNG (lossless). Choosing JPG or WebP with a lower quality gives the biggest file-size savings.
How do I resize an image for Instagram or YouTube? +
Resize to the platform’s exact pixels — for example 1080 × 1080 for an Instagram square post or 1280 × 720 for a YouTube thumbnail. See our image-size pages for every platform’s dimensions.