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JPEG to PNG Converter
This free JPEG to PNG converter turns your JPG and JPEG photos into lossless PNG images right in your browser. Drop in a photo, and download a PNG that keeps every pixel exactly — ready to edit, print, or hand to any tool that only accepts PNG files. Your image never leaves your device: the whole conversion runs on your own computer, with no upload, no queue, and no sign-up.
All processing happens in your browser. Your image is never uploaded to any server. Need the reverse direction? Our PNG to JPG converter turns a PNG back into a smaller JPEG file.
How it works
JPEG and PNG are the two most common picture formats, and they make opposite trade-offs. JPEG was built for photos: it compresses hard, throwing away fine detail the eye barely notices, so a photo that would be megabytes as a PNG fits into a few hundred kilobytes as a JPEG. The cost is that JPEG is lossy — every time the picture is opened, edited, and saved again as a JPEG, a little more detail is lost. PNG makes the opposite deal: it stores every pixel exactly and never loses anything, which makes its files much bigger for photos, but means the picture can be edited and saved as many times as you like without any further damage.
That is the whole point of this converter. It decodes your JPEG into its full grid of pixels, then writes those pixels out as a PNG. The picture itself does not change — the PNG looks exactly like the JPEG, because converting cannot bring back detail that JPEG compression already removed. What changes is what happens next: from here on, the picture is lossless. Crop it, add text, adjust the colours, save it again, and the pixels stay exactly as they are, instead of picking up fresh compression damage with every save.
The resize option trims the picture's dimensions before converting, which is the one way to make the PNG smaller. A photo that will only be shown 800 pixels wide does not need to be stored at 1920 pixels, so choosing "Max width 800 px" cuts the file down before it is written as a PNG. The picture is only ever shrunk, never stretched, and its proportions are kept exactly, so nothing is squashed or stretched out of shape. The background option matters only in one case: JPEG pictures are always fully solid, with no transparency, so "Keep as pictured" and "Flatten onto white" give the same result for an ordinary photo. The choice is there for consistency with the other image converters on this site.
Before converting, the tool checks that your file really is a JPEG. It reads the first bytes and looks for the JPEG signature — the two-byte marker (FF D8) every genuine JPEG starts with, followed by the JFIF or Exif marker a camera or phone writes. A PNG or a text file renamed to end in .jpg fails that check and is rejected with a friendly message instead of producing a broken file. Files that pass are drawn onto a canvas in your browser and encoded as PNG with the browser's own image encoder. Nothing is uploaded at any point, so the conversion works with no internet connection once the page has loaded, and your photos stay private.
The finished file is named from the file name box — by default image.png — and downloads straight to your computer. Use the PNG wherever a lossless file is needed: editing in a photo editor, printing, uploading to a site that only accepts PNG, or archiving a picture you plan to work on later. If the large file size is a problem, keep the JPEG as your small sharing copy and use the PNG only as the editing master — that way you get the best of both formats.
Worked example
A photographer has a detailed photo saved as photo.jpg, 1200 × 800 pixels and 860,897 bytes (about 841 KB). She wants to edit it — cropping, adding a caption, and adjusting the colours — and she knows that saving it as a JPEG after every edit would slowly wear the picture away.
Step 1: She drops photo.jpg onto the converter. The tool checks the JPEG signature, reads the picture, and shows a preview. The result line reads "photo.jpg ready — 1200 × 800 pixels".
Step 2: She keeps the default settings: original size, background kept as pictured, file name "image".
Step 3: She presses Convert to PNG. The JPEG is decoded to its full grid of pixels and written out as a PNG.
Step 4: She presses Download .png to save the file as image.png.
The result is a PNG file of 2,878,444 bytes (about 2.74 MB) at the same 1200 × 800 size — roughly 3.3 times the size of the 841 KB JPEG, which is normal, because PNG stores every pixel exactly instead of compressing the photo. The picture looks identical to the JPEG, but now she can edit and re-save it as many times as she likes without losing any more quality.
FAQ
Why would I convert a JPEG to a PNG?
Convert a JPEG to PNG when you need to edit a picture without losing more quality, or when a tool, printer, or website only accepts PNG files. PNG is lossless, so once the picture is a PNG, every later edit and save keeps exactly the same pixels instead of adding fresh JPEG compression damage each time.
Will the PNG look better than the JPEG?
No — the PNG will look exactly the same as the JPEG. Converting cannot bring back detail that JPEG compression already removed. What PNG gives you is a clean starting point: the picture will not get worse with further edits and saves, the way a JPEG does each time it is re-saved.
Why is the PNG file much bigger than the JPEG?
JPEG compresses photos very aggressively and throws away fine detail to save space, while PNG stores every pixel exactly. The same 1200 by 800 photo can be 841 KB as a JPEG and 2.74 MB as a PNG. The bigger file is the price of lossless quality, and it is normal for photos.
Does the PNG support transparency?
The PNG format supports transparency, but a JPEG has no transparency to carry over — every pixel in a JPEG is fully solid. The converted PNG will have a solid background, exactly like the JPEG. To get a transparent picture, start from a PNG or another format that already has transparency.
Are my images uploaded to a server?
No. Your JPEG is decoded and re-encoded as PNG entirely in your browser, using JavaScript running on your own device. Nothing is uploaded, so photos and private images stay on your computer.