Image Resizer canvas
Resize images in the browser and save as PNG, JPEG, or WebP, with aspect ratio locking.
What this tool does
Shrinking an image comes up constantly: hitting an upload limit, needing a thumbnail, or trimming an oversized screenshot for a document. Opening an editor for that is tedious, and uploading work material to an online service is worse.
This tool resizes with the browser canvas. Selecting a file fills in the original dimensions, and changing either width or height updates the other to preserve the ratio. Common widths are available as preset buttons.
The output format is selectable as well. Saving as JPEG paints a white background first so transparent areas do not turn black. The resulting file size and the area relative to the original are displayed so you can see immediately how much was saved.
When to use it
Use it to fit a photo inside an upload limit, to size images for a blog post or document, to produce a thumbnail quickly, or to scale down a screenshot for documentation.
Input and output examples
A 3000Γ2000 photo with the 800 preset
800Γ533 with the ratio preserved
Changing the width recalculates the height automatically.
Saving as JPEG
Transparent areas filled with white
JPEG has no transparency channel.
Notes and limitations
Enlarging an image cannot invent detail that was never captured, so the result is simply blurry; find a larger original instead. Photo metadata (EXIF) is also lost when the image passes through canvas, so keep the original if capture date or location matters. That same behaviour makes this a convenient way to strip location data before sharing a photo. Very large images consume significant browser memory and may process slowly.
Frequently asked questions
Does enlarging improve quality?
No. Missing detail cannot be created, so the image only becomes blurry. Start from a larger original.
Is EXIF metadata preserved?
No. Redrawing through canvas discards it, so keep the original if you need the capture information.
Is my file uploaded?
No. Everything happens in the browser with no network request.