About the Image Format Converter
This image converter changes a photo or graphic from one file format into another — PNG, JPEG or WebP — using the Canvas API built into your browser, so the conversion happens on your device rather than on a server. It handles the one tricky part of format conversion automatically: filling transparent areas with a background colour of your choice when converting to a format that does not support transparency.
How to use the Image Format Converter
- 1
Upload the image you want to convert.
- 2
Choose the format to convert to from the dropdown.
- 3
If converting to JPEG or WebP, set the quality; if your source has transparency, pick a background colour.
- 4
Download the converted file once the preview shows the result you want.
What people use it for
Adding transparency support
Convert a JPEG logo to PNG before placing it over a coloured background, so the rectangular white edge disappears.
Modernising a photo for the web
Convert a large PNG photograph to WebP or JPEG to cut its file size dramatically while keeping acceptable visual quality.
Meeting a platform's format requirement
Some upload forms only accept JPEG or only accept PNG. Convert whatever format you have into the one that is actually required.
What each format is actually for
PNG uses lossless compression and supports an alpha channel for transparency, which makes it the right choice for logos, icons, screenshots and any graphic with sharp edges or text. JPEG uses lossy compression tuned for photographs, discards an alpha channel entirely, and produces much smaller files for photos than PNG can. WebP, developed by Google, supports both lossy and lossless modes plus transparency in one format, and generally produces smaller files than JPEG at equivalent visual quality, though a small number of older tools and email clients still handle it poorly. Choosing the right format for the content, rather than defaulting to one format for everything, is where most of the practical file-size gain comes from.
What happens to transparent pixels
When converting to a format without an alpha channel, every fully or partially transparent pixel needs a real colour to fall back to, because JPEG has no concept of 'no colour here'. This tool paints the chosen background colour behind the image before flattening it, the same way opening a transparent PNG in a printed document would show whatever the page colour is. White is the safe default for most uses; picking a colour that matches where the image will actually be displayed avoids a visible rectangle around a previously transparent logo.
Tips
- Converting a JPEG to PNG does not restore quality lost during the original JPEG compression — it only stops further loss from that point on.
- For icons and logos with flat colour and sharp edges, PNG usually beats JPEG on both quality and file size.
- Test WebP output in your actual target environment before switching a whole workflow to it.