Free Image Format Converter

Worked example

Press "Try a sample image". It adds sample-photo.png, a 1600 × 1000 PNG. In the "Convert to" list "JPG" is selected and "Quality" is 90%. Press "Convert 1 image". The row goes from "Waiting" to "Done", followed by the new size and a "% smaller" note, and a Before and After comparison appears with the two sizes joined by an arrow. "Download all (1)" saves sample-photo.jpg. Now open "Resize (optional)", choose "Max width" and type 800. Press "Change settings and convert again", then "Convert 1 image" once more. The picture is scaled to 800 × 500, keeping its shape. Pick "PNG" and convert again: "Quality" is greyed out with "PNG is lossless — quality setting doesn't apply." and the file is sample-photo.png.

Which settings to use, and the limits

• Choose the output format on purpose. "Convert to" lists "JPG", "PNG", "WebP", "AVIF" and "Original format". AVIF appears only if your browser can write it; otherwise the page says "AVIF export is not available in this browser. WebP gives similar savings and opens almost everywhere." The tool starts on JPG, but if the first files you add are all JPEG and you have not picked a format, it switches to PNG so that a JPEG is not saved as a JPEG again. "Original format" keeps each file's type when a canvas can write it, and turns GIF, BMP and SVG into PNG. A note under the buttons explains the trade-off of the format you picked.
• Set Quality for JPG, WebP and AVIF. The "Quality" slider runs from 1 to 100 percent, from "Smallest" to "Best", and starts at 90%. The page says "Around 90% looks the same as the original at a much smaller size. 100% often makes the file larger." PNG ignores it: the slider is greyed out. After a conversion, a row notes "12% smaller" when the new file is at least 1% smaller, and "12% larger. Lower the quality or try WebP" when it is at least 5% bigger. Between those two, no note is shown.
• Use Resize only when you need a smaller picture. "Resize (optional)" starts on "Original size". "Max width" and "Max height" only shrink: an image larger than your number is scaled down with its proportions kept, and a smaller image is left alone. "Percent" scales every image by that share, so 50 halves each side and 200 doubles them. An empty number box means no resizing. The arrows stop at 10,000 px or 400 percent, but a bigger number you type is accepted. Resize does not apply to SVG files.
• Know what happens to HEIC, GIF and SVG files. An iPhone HEIC or HEIF photo is converted to PNG as you add it ("Converting your iPhone photo…"), then converted again to the format you chose. An animated GIF is flattened, and an amber note says "Animated GIFs are flattened — only the first frame is converted." An SVG has no pixel size, so "SVG output width" appears, starting at 1024 px and going up to 8000 in steps of 64, and the height follows the drawing's proportions. BMP files are accepted too.
• Drop several images to convert them together. With more than one file the button reads like "Convert 3 images", and two files are converted at a time. "Stop" ends the run, and while it is running "Download 2 of 5 (so far)" saves what is finished. "Download all (5)" gives a ZIP named converted-jpg.zip, or converted-images.zip for "Original format". Each file keeps its name with the new ending, such as photo.jpg; if two names match, the ZIP uses photo (2).jpg. A file added twice, with the same name, size and date, is counted once.
• Change the settings without adding the files again. When every row has finished, "Change settings and convert again" puts the same files back in the queue, so you can try another format, quality or size. To load a picture, drop it, press "Browse files", or paste it with Ctrl+V; the page says "Tip: paste an image from your clipboard (Ctrl+V) to load it instantly." and hides this on touch screens. The conversion happens on a canvas in your browser and nothing is uploaded. The one exception is "Or paste a file URL", which makes your browser fetch that address.

Common problems and how to fix them

It says "Could not convert this file. It may be corrupted or unsupported."

This appears on the file's row when the browser could not open the picture, draw it, or encode it. Open the file in another program and save it again as JPG or PNG, then add it again. A very large output size can also fail, such as a high "Percent" or a big "SVG output width"; lower it and press "Retry failed (1)", then the convert button.

It says "This browser cannot export that format. Pick another one."

Browsers quietly fall back to PNG when they cannot write the type you asked for. The tool checks the type of the file it got and refuses to give you a PNG labelled as something else. Pick "JPG" or "PNG" under "Convert to", press "Retry failed (1)", and then press the convert button. WebP and AVIF buttons are shown only when a test shows that the browser can write them.

It says "scan.tif is a TIFF file, which this tool can't open."

The drop zone looks at the first bytes of the file, not only its name, and names what it found. This tool opens JPG, PNG, WebP, AVIF, GIF, BMP, SVG and HEIC/HEIF. TIFF is not on the list, and neither is PDF. Convert the file to one of the accepted types in another program first. A file with an unaccepted name whose type cannot be identified is refused with "File type not supported:" and its name.

A row says "12% larger. Lower the quality or try WebP".

The new file is at least 5% bigger than the original. This is common when a JPG becomes a PNG: PNG keeps every pixel exactly, so a photo takes more space. It also happens with JPG at 100%. Choose "WebP", or JPG with "Quality" near 90, and convert again. If you only wanted a different file type and not a smaller file, you can ignore the note.

Transparent areas turned white.

JPEG cannot store transparency, so the tool paints white behind the picture before saving it, and the page warns "Transparent areas become white." Choose "PNG", "WebP" or "AVIF" under "Convert to" to keep see-through areas. The PNG note says "Transparency is preserved."

How it compares

This tool changes the file type and, if you ask, the pixel size. It does not edit the picture: there is no crop, rotate, retouch or colour change, and no exact file-size target. For an exact size in pixels or kilobytes, use the Image Resizer. Every file is redrawn on a canvas and encoded again, so JPG, WebP and AVIF lose a little quality each time, and details such as camera information are not carried over. It cannot write GIF, BMP, TIFF or animated files, and an animated GIF keeps only its first frame. A desktop image program can handle more formats and options. In exchange nothing needs installing, iPhone HEIC photos and SVG files are accepted, and your pictures stay in your browser.