Image Converter & Resizer
Convert between PNG / JPEG / WebP and shrink dimensions. Runs on-device.
Drop an image here, or click to choose a file.
PNG · JPG · WebP · GIF — nothing is uploaded.
How to convert or resize an image
- Add your image. Drop it onto the box, or click to choose a file.
- Set your options. Pick the output format (WebP, JPEG or PNG), an optional max width, and a quality level.
- Convert and download. Click "Convert," then save the result.
What happens to your image
Conversion happens entirely in your browser using the Canvas API — the image is never uploaded to OpenToolkit.
What this converter supports
Common reasons to convert an image
- Shrink a photo before attaching it to an email or upload form.
- Convert a PNG screenshot to a smaller JPEG or WebP file.
- Resize an oversized image down to a reasonable width for the web.
- Standardize an image to a specific format before using it elsewhere.
Frequently asked questions
Is my image uploaded anywhere?
No. Conversion runs entirely in your browser tab using the Canvas API.
Which format should I pick?
WebP is usually smallest at a given quality and is well suited to the web; JPEG is the most universally supported; PNG preserves transparency and pixel-exact detail but has no quality slider since it isn't lossy the same way.
Does resizing crop my image?
No — setting a max width scales the image down proportionally; it doesn't crop it.
Can I enlarge an image with the max-width setting?
No — max width only shrinks an image that's larger than the value you set. Entering a width larger than the original leaves the size unchanged rather than upscaling it.
Why is there no quality slider for PNG?
PNG is a lossless format, so there's no quality trade-off to adjust the way there is for JPEG or WebP.
Is there a file size limit?
No fixed limit — a very large image is bound only by your browser's available memory.
Last reviewed: August 2026