How to Convert Images to WebP (JPG and PNG)

Quick answer: To convert an image to WebP, open it in a converter, save it with the WebP encoder and check that the result is smaller and still looks right. The free WebP Converter turns a JPG or PNG into a WebP file in your browser at a fixed 88% quality, without uploading it.

What WebP is

WebP is an image format developed by Google. It supports lossy compression (based on VP8 video coding), lossless compression, transparency (an alpha channel) and animation, all in one format. The format is described in the WebP documentation on developers.google.com and published as RFC 9649.

Google's documentation reports that lossless WebP files are 26% smaller than PNGs and lossy WebP files are 25 to 34% smaller than comparable JPEGs at the same SSIM quality. Your own results depend on the image, so always compare the actual file sizes.

All current major browsers display WebP. The maximum size is 16383 × 16383 pixels.

How to use the free WebP Converter

1. Under JPG or PNG image, choose the file you want to convert. The file picker accepts JPG and PNG only.
2. Click Convert to WebP.
3. Check the preview and the file size shown in KB.
4. Click Download WebP. The file is saved as converted.webp; rename it to something descriptive.

What the tool does:

• Keeps the original pixel dimensions. Resize separately if the image is larger than you need.
• Encodes lossy WebP at 88% quality. There is no quality slider or lossless option.
• Keeps PNG transparency, because the canvas is not filled with a background color.
• Converts one image at a time.

The conversion runs in your browser using the canvas encoder, and the image is not uploaded.

When WebP is and is not worth it

WebP is mainly for the web. Some email clients, office programs and upload forms do not accept it, so send JPG or PNG there.

Worked example: a hero image with a fallback

A website uses hero.jpg, 1600 × 900 pixels. You convert it with the tool, rename converted.webp to hero.webp, and compare the two sizes. If the WebP file is smaller and looks the same, serve it with the original as a fallback:

<picture>
  <source srcset="hero.webp" type="image/webp">
  <img src="hero.jpg" alt="Team at work" width="1600" height="900">
</picture>

Browsers that support WebP load hero.webp. Any that do not, ignore the source element and load the JPG. The width and height attributes let the browser reserve space before the image loads.

Lossy and lossless WebP

Lossy WebP discards some detail the eye is unlikely to notice, much like JPG. Lossless WebP keeps every pixel exactly, like PNG. The encoder in this tool always produces lossy WebP at 88% quality, which suits photographs and most illustrations.

For images where every pixel matters, such as UI screenshots, pixel art or diagrams with fine lines, compare the WebP result with the original at 100% zoom. If you see soft edges or color fringes around text, keep the PNG, or use a desktop encoder such as Google's cwebp command-line tool with its -lossless option.

Converting does not change the pixel dimensions. A 4000-pixel-wide photo stays 4000 pixels wide, so resizing it to the size your page needs often saves more than the format change alone.

Common mistakes

• Converting an image that was already compressed many times. Each lossy step adds artifacts. Convert from the best original you have.
• Converting the same file repeatedly. Do not convert a WebP back to JPG and then to WebP again. Keep the originals.
• Not checking transparency. Transparency is kept, but check the edges of logos and cut-outs on both light and dark backgrounds.
• Not checking the result. If a browser cannot encode WebP from a canvas, the HTML standard tells it to produce a PNG instead. Use a current version of Chrome, Edge or Firefox and confirm the file really is smaller.
• Removing the only JPG or PNG copy. Keep the original for print, email and tools that do not read WebP.