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Resize and convert an image

Change the pixel size of a PNG, JPEG or WebP image and save it as PNG, JPEG or WebP, entirely inside this browser tab. The aspect ratio is always preserved, the file you selected is never modified, and the format that is actually produced is reported rather than assumed.

Your image stays in this browser

The image you select is decoded and re-encoded by this page only. Nothing is uploaded, no external API is called, and neither the file name nor the image is written to the address bar, to cookies or to browser storage. Closing the tab discards everything. You can confirm this by opening your browser developer tools on the Network tab before you convert an image.

Convert an image

1. Choose an image

Static PNG, JPEG and WebP only, up to 20,971,520 bytes (20 MiB) and 40 megapixels. Larger or unsupported files are refused with a message rather than partly read.

2. Size

Fill in one box to scale by that edge, or both to fit the image inside that box. The aspect ratio is always kept, so the result can be smaller than the box on one edge. Each edge is limited to 12,000 px.

Off by default. Enlarging cannot add detail that is not in the source; it only produces a larger file.

3. Output format

What can be opened

Static PNG, JPEG and WebP images are supported, because those are the formats a browser can reliably decode and re-encode without extra software. A file name and the type your system reports are not evidence, so the first part of the file itself is read and its container is identified before anything is decoded. A file whose contents are GIF, BMP, TIFF, ICO, PDF, SVG, HEIC/HEIF or AVIF is refused and named, whatever it was called. An animated WebP and an animated PNG (APNG) are recognised from their own header and refused: a browser would hand back the first frame, and this tool will not discard an animation on your behalf. If the first 256 KiB and the bounded header scan cannot establish the dimensions and rule out animation, the file is refused before decoding. This can include valid images with unusually large metadata; use an image editor that supports the original format in that case.

Metadata, animation and colour

The image is decoded to pixels and encoded again, so EXIF data such as camera model, date and GPS location is not carried into the output. Treat that as a side effect, not as a guaranteed privacy feature: this tool does not verify what the browser writes, and it is not an EXIF scrubber. Embedded ICC colour profiles are likewise not preserved, so wide-gamut images can shift in appearance. Orientation is requested from the decoder, and if the browser does not support that request, it is reported with the result.

Limits of this tool

  • Input is limited to 20,971,520 bytes (20 MiB) and 40 megapixels; each output edge is limited to 12,000 px.
  • Only the aspect ratio of the source is offered. There is no cropping, rotation, watermark or filter.
  • Encoding is done by the browser. The same settings produce different bytes in different browsers, and quality numbers are not comparable between formats.
  • Converting an image does not always make it smaller. The measured input and output sizes are shown, including when the file grows.
  • The output is re-encoded, so it is never byte-identical to the source, even at the same format, size and quality.
  • The original file on your computer is never changed. Saving the result creates a new file.

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