Image Resizer
Resize an image to exact pixel dimensions or a percentage locally in your browser — files never leave your device. Aspect ratio can be locked to avoid distortion.
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Resize your image locally
No upload or network request — files never leave your device. Animated images become a single frame and metadata (EXIF) is not preserved.
What this tool does
Resize an image to exact pixel dimensions or a percentage locally in your browser — files never leave your device. Aspect ratio can be locked to avoid distortion. Processing happens in the ImageTools panel below: enter the target size there (the numbers above document the example). Enlarging beyond the original size cannot add real detail. Inputs are capped at 30 MB / 40 megapixels.
How to use the Image Resizer
- Enter or select target width (px).
- Enter or select target height (px).
- Read the calculated result; change any measurement to compare alternatives.
Formula
Draw the decoded image to a Canvas of the requested width and height (or a percentage scale of the original) and export a local download at the original format.
- width
- Target width (px)
- height
- Target height (px)
Processing happens in the ImageTools panel below: enter the target size there (the numbers above document the example). Enlarging beyond the original size cannot add real detail. Inputs are capped at 30 MB / 40 megapixels.
Worked example
For image resizer, the following measurements illustrate the exact method: Target width (px): 800; Target height (px): 600.
Inputs
- Target width (px)800
- Target height (px)600
Result
- ResizeSelect a local image in the panel below to resize it (example target 800x600 px) and download it.
Results explained
- Resize
- Resize from the formula above. Processing happens in the ImageTools panel below: enter the target size there (the numbers above document the example). Enlarging beyond the original size cannot add real detail. Inputs are capped at 30 MB / 40 megapixels.
Frequently asked questions
It scales height automatically from the width you enter (and vice versa) using the original width:height proportion, so the resized image is never stretched or squashed.
No tool can add detail that was never captured. Browser resizing smooths enlarged pixels, which looks soft; for print or large displays, start from the largest original available.
The resizer keeps the source format (PNG stays PNG, JPEG stays JPEG). Use the Image Format Converter instead when you need to change format at the same time.
No. Files are decoded and re-encoded with the browser Canvas API on your device. There is no upload, no server and no network request — you can verify by processing an image while offline.
Canvas re-encoding does not copy EXIF, GPS or camera metadata into the output — a privacy benefit, but copy any metadata you need before converting.