1. You pick a file
When you drop a file onto the page or click the upload area, your browser hands the file to the JavaScript running on the page. It does not send the file to any server. You can verify this by opening your browser's developer tools, switching to the Network tab, and watching what happens when you drop a file — no upload request appears.
2. The browser decodes it
Modern browsers can decode JPG, PNG, WEBP, GIF, BMP, HEIC, AVIF and TIFF directly. We use the standard HTMLImageElement, createImageBitmap, and the Canvas 2D API to read the pixel data into memory. For HEIC, we use a lightweight WebAssembly decoder that runs inside your browser too.
3. Conversion or transformation happens locally
Once the pixels are decoded, we apply whatever you asked for — re-encoding to a different format, scaling to a different size, cropping to an aspect ratio, or reducing quality to a target file size. All of this runs on your CPU, in your browser tab.
4. You download the result
The output file is written to a blob in memory, then offered to you as a download. When you close the tab, the blob is discarded. There is no server-side copy because nothing was ever sent server-side.
What we do collect
The page itself loads HTML, CSS, JavaScript, and ads. Standard request logs (page URL, IP address, browser version) are kept temporarily by our hosting provider for security and abuse prevention. We use Google Analytics to understand which tools are popular, in aggregate, and Google AdSense to display the unobtrusive ads that fund the site. Neither receives your image files. The details are in our Privacy Policy and Privacy & Security pages.
Limitations
- Very large files (over ~100 MB) may run out of browser memory on older devices.
- Some animated formats can only be exported as a static first frame when converting to JPG or PNG.
- Browser support for HEIC and AVIF varies — we fall back to WebAssembly decoding where needed.
- If your browser is in Private/Incognito mode with extensions blocking storage, performance may suffer.
Supported formats
Inputs: JPG, PNG, WEBP, BMP, GIF, HEIC, AVIF, TIFF. Outputs: JPG, PNG, WEBP, BMP, GIF, AVIF, PDF. Browse the full tools directory to see every supported conversion.