About Image Format Converter
Image Format Converter rewrites an image from whatever format it is in into one of the three formats the web actually uses: PNG for lossless output and transparency, JPEG for photographs and maximum compatibility, and WebP for the smallest file at a given quality.
The choice between them is a trade rather than a preference. PNG keeps every pixel exactly and supports transparency, at the cost of size on photographic content. JPEG discards fine detail to save bytes and cannot store transparency at all. WebP does both jobs reasonably well and is the usual answer when nothing outside the browser will read the file.
One consequence of choosing JPEG deserves a warning, because it is invisible until it is too late. Transparency has no representation in JPEG, so any transparent area of the source is rendered as a solid colour — conventionally black — rather than as transparency. If the picture needs to sit on a coloured background, convert to PNG or WebP instead, or produce a version with the background already flattened in the colour you want. Metadata is not carried into the converted file.
How to use Image Format Converter
- 1 Choose the source image and note whether it has any transparent areas.
- 2 Select the target format: PNG, JPEG or WebP.
- 3 Download the converted file, whose name takes the extension of the new format.
- 4 Check any transparency in the original if you chose JPEG, since it will not survive.
Frequently asked questions
Why did my transparent background turn black?
Because JPEG has no way to store transparency, so transparent pixels are written as a solid colour, normally black. Choose PNG or WebP to keep transparency, or flatten the image onto the background colour you want before converting.
Does converting to PNG make an existing JPEG look better?
No. Converting to a lossless format preserves what is there now; it cannot restore detail that the JPEG encoding already discarded. Choose PNG for images with flat colours, text or transparency, not as a repair for a compressed photo.
What quality is used for the lossy formats?
A high quality setting, so the conversion is designed to be visually faithful rather than aggressively small. For control over the trade between size and appearance, use the compress tool, which exposes the quality percentage directly.
Is the image uploaded anywhere?
No. The conversion runs on a canvas inside your browser and the file never leaves the device, which is why it works even with the network disconnected. It is also why very large images depend on your own machine memory rather than a server limit.
Free, online, and private
Free to use
Image Format Converter is completely free. There is no account to create, no login, and no hidden charge or usage limit.
Runs online in your browser
It is a free online tool that runs entirely in your browser. Nothing to download or install — open the page and start using it right away.
Your data stays private
All processing happens locally on your device. Your input is never uploaded, stored, or tracked, so it never leaves your browser.
How Image Format Converter behaves in detail
These are the specifics of this implementation — the exact ranges, defaults and fixed settings you are working with.
| Parameter | Value |
|---|---|
| Format options | 3 values in the dropdown — PNG (default), JPEG and WebP |
| What is actually encoded | each option reaches its own encoder: the type table maps png, jpg/jpeg and webp, so PNG writes image/png, JPEG writes image/jpeg and WebP writes image/webp |
| Encoder quality | fixed at 0.92 for the lossy path — the run function passes no quality of its own |
| Dimensions | unchanged — the canvas is built at the source image's natural width and height |
| Filename | the original base name with the extension replaced by the type actually produced, so the JPEG option saves a .jpg and the WebP option a .webp |
Compiled from the implementation of this tool and checked against it by itoolnet.
What Image Format Converter does not do
Knowing the edges of a tool saves more time than another list of its features. These are the cases where it will not do what you might expect.
- Transparency is flattened on the JPEG path. The image is drawn onto a blank canvas before encoding and JPEG carries no alpha channel, so a transparent region is filled in by the encoder with no say from you — a logo with a transparent background will not come back with it intact.
- Only the container changes: nothing is resized, no quality can be set and no output size can be requested. Turning a small JPEG into PNG usually inflates it, and the page shows no byte figure for either the input or the result.
- PNG, JPEG and WebP are the only outputs on offer. GIF, BMP, TIFF, AVIF and SVG are absent, and because everything is drawn onto one canvas the pipeline holds a single frame, so an animated input comes back as a still image.
Tested and documented by itoolnet, the team that builds and maintains this site.