Resize photo dimensions to your target width and height in pixels. Lock the aspect ratio to prevent image stretching, preview output details live, and download instantly. 100% private.
Images stay in your browser. Nothing is uploaded to any server.
How It Works
Resizing photo dimensions is a key task when fitting graphics onto online forms, resizing banners for social channels, or scaling screenshots. By resizing dimensions locally, you bypass the risk of file storage leaks on cloud servers.
This dimension resizer works entirely inside your browser tab using the HTML5 Canvas API. The script creates an off-screen canvas at your exact target width and height, draws the source photo onto it using bi-linear interpolation, and outputs the resized blob instantly. No files leave your device.
Leaving the **"Lock aspect ratio"** checkbox selected is highly recommended. It calculates the height automatically when you adjust the width, and vice versa. This keeps the photo proportions correct, preventing your face or document text from looking stretched or distorted.
Reducing the pixel dimensions of a photo (e.g. from 4000x3000px down to 800x600px) is the most effective way to shrink the file size. For direct file-size targets in KB/MB, try our **[File Size Compressor](/tools/image-resize-size)**.
No. Our tool processes everything inside your local device memory using JavaScript. All rendering, canvas manipulation, and saving steps occur locally on your processor, keeping your pictures completely secure.
Yes. You can increase the width and height inputs above original values. However, scaling up will resample existing pixels, which can make the image look softer or slightly blurry depending on the scale ratio.
The resizer preserves the format of the uploaded file (JPG or PNG). If you upload a transparent PNG, it retains its transparency. If you upload a JPG, it outputs an optimized JPG.