02 / image-resizer
free online tool
Image Resizer
Resize images to any dimension instantly in your browser.
Drop an image here or click to upload
how to use
- 01
Upload an image by dropping it or clicking to browse.
- 02
Enter the desired width and/or height in pixels.
- 03
Click 'Resize' and download the resized image.
about
What is this tool?
Image Resizer lets you change the dimensions of any image directly in your browser. The Canvas API draws and scales the image to your specified dimensions, producing a downloadable JPEG output — all without any server interaction.
why use this tool
- -Resize images instantly with no upload.
- -Maintain aspect ratio automatically.
- -Perfect for preparing images for web, email, or social media.
- -Free with no watermarks or limitations.
features
- -Custom width and height input.
- -Aspect ratio lock option.
- -Outputs as JPEG for broad compatibility.
- -Real-time dimension preview.
comparison
Common Image Dimensions by Platform
| Platform | Recommended Size | Notes |
|---|---|---|
| Instagram Post | 1080 × 1080 px | Square format |
| Facebook Cover | 820 × 312 px | Cropped on mobile |
| Twitter/X Header | 1500 × 500 px | Banner image |
| YouTube Thumbnail | 1280 × 720 px | 16:9 ratio |
All processing happens entirely in your browser using JavaScript. No files, text, or data are ever sent to a server. Your data stays on your device.
✦ tip from dragontail
One thing I learned while optimising Dragontail's landing pages: always resize images to their display size before uploading — a 4000 px photo displayed at 800 px still downloads at full size. Resizing first can cut load time by 60% with zero visual compromise.
faq
Will my image be uploaded anywhere?
No. Everything runs locally in your browser using the Canvas API.
Can I resize to a very large size?
Yes, but very large canvases may be limited by your browser's memory. For typical web dimensions this is not an issue.
Does resizing reduce quality?
Scaling up (enlarging) can reduce sharpness. Scaling down generally preserves quality well.