Convert Image
Change an image between JPG, PNG and WebP in your browser, with a warning before transparency is lost.
Processed on your device — no upload
How to convert image
- Choose the image you want in a different format.
- Pick the target format, and a quality if it is a lossy one.
- Download the converted file.
How it works
Converting decodes the image into raw pixels, draws them onto a canvas, and encodes them again in the format you asked for. Your browser already contains encoders for JPEG, PNG and WebP, so no library is downloaded and nothing is sent anywhere.
The three formats are not interchangeable, and the differences matter. PNG is lossless and supports transparency: perfect for screenshots, logos and line art, wasteful for photographs. JPEG is lossy with no transparency: the opposite trade-off, excellent for photographs and poor for sharp-edged graphics, where it produces halos around text. WebP does both jobs — lossy or lossless, with transparency either way — and is typically 25–35% smaller than the equivalent JPEG.
One conversion is lossy in a way people do not expect: PNG to JPEG. Transparent areas cannot survive, because JPEG has no alpha channel, so they are filled with white before encoding. A logo converted this way gains a white box around it. The tool warns you when that is about to happen and points you at WebP instead.
Converting a JPEG to PNG does not restore anything. The detail JPEG discarded is gone; you get a lossless copy of a lossy image, which is simply a much larger file containing the same picture including its artefacts.
A worked example
A designer sends you logo.png, 1400×400 with a transparent background, 240 KB. You need it for a website and want it smaller.
Choose the file. The tool defaults the target to JPEG — and immediately warns that JPEG has no transparency and the transparent area is being filled with white. Look at the preview: the logo now sits in a white rectangle, which will show as an ugly block against your page background.
Switch to WebP at quality 90. The result is about 42 KB — six times smaller than the PNG — and the transparency is intact. The preview sits on a chequerboard so you can see the transparent areas rather than guessing.
Now the reverse case. You have screenshot.jpg, a 900 KB screenshot of a code editor. Converting it to PNG produces roughly 2.1 MB — larger, because PNG stores every pixel exactly, including the JPEG artefacts already baked around the text. The right move is to capture screenshots as PNG in the first place; converting afterwards cannot undo what was lost.
If your aim is a smaller file rather than a different format, compressing gives you a quality slider and shows the saving as you drag.
Questions
How do I change format between image types?
Pick the target and the picture is decoded and written again in the new one. Every common web format is here: JPEG, PNG, WebP and AVIF where the browser supports it.
How do I convert JPG to PNG, or PNG to JPG?
Pick the target format and the picture is redrawn into it. Going to PNG will not recover detail a JPG already lost, and png to jpg discards transparency, so anything see-through becomes white.
Does changing the file type re-encode the picture?
Yes. Every conversion here decodes the image and encodes it again, so this is a real transcode rather than a renamed extension.
Is my image uploaded to convert it?
No. The encoders are built into your browser and the work runs on your own device. This site is static files with no backend, so nothing is transmitted.
Which format should I choose?
PNG for screenshots, logos and anything needing transparency. JPEG for photographs that older software must open. WebP for almost everything on the modern web — it does both jobs and is smaller than either.
What happens to transparency when I convert to JPEG?
It is lost. JPEG has no alpha channel, so transparent areas are filled with white before encoding. Choose WebP if you need transparency in a small file.
Will converting a JPEG to PNG improve its quality?
No. The detail JPEG discarded is gone permanently. You get a lossless copy of a lossy image — a much larger file showing exactly the same picture, artefacts included.
Is WebP safe to use?
Yes. Every current browser supports it, including Safari. The only reason to avoid it is older desktop software or a workflow that expects JPEG specifically.
Can I convert HEIC photos from my iPhone?
Only if your browser can decode HEIC, which most cannot. On an iPhone, set Camera to "Most Compatible" to capture JPEG, or export a JPEG from Photos before converting.
Does converting remove the photo metadata?
Yes. The image is redrawn through a canvas, which carries pixels only, so EXIF including GPS does not survive the conversion.
Can I convert animated GIFs?
The first frame only. Animation is not carried into JPEG, PNG or WebP by this tool — you would get a single still image.
Which conversions does this actually do?
JPG, JPEG, PNG and WebP in any direction. Convert JPG to PNG when you need transparency or a lossless copy; convert PNG to JPG when the file is a photograph and the size matters more than the alpha channel. Converting an image never improves it — it re-encodes what is already there.
Is changing an image format the same as converting it?
Yes — change image format and convert images are one thing. Change JPG to PNG when you need transparency, change PNG to JPG when the file is a photograph and size matters. Convert pictures between JPEG, PNG and WebP in any direction; converting never improves what is already there, it only re-encodes it.
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