Images & documents
Free Image Resizer
Resize a PNG, JPEG or WebP image to exact pixel dimensions in your browser and convert between formats. No upload, no watermark.
How to use this tool
- Choose an image and enter the width or height; the other dimension follows when the aspect ratio is locked.
- Pick PNG, JPEG or WebP as the output format.
- Resize and download the result.
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Open tool ↗Frequently asked questions
Image resizer
questions.
What size should form or profile images be?
For upload previews and avatars, 400 to 800 pixels on the long side is plenty. Smaller files upload faster and keep submissions light.
Which format keeps the smallest file?
WebP is usually smallest, JPEG suits photos, and PNG keeps sharp edges and transparency. Compare the reported size after resizing.
Is anything I enter saved or sent to Form Koi?
No. Everything you type or upload stays in this browser tab and is processed locally. Copy or download anything you want to keep before leaving the page.
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