Why convert a JPG to PNG at all
Most of the time a JPG is the right file for a photo: it is small and everything opens it. People still need a PNG copy for a handful of everyday reasons. An upload form or a print shop accepts PNG only. You want to edit a picture several times without each save blurring it a little more. Or you want the white box around a logo or a signature to disappear so it sits cleanly on a coloured slide, a T-shirt design or a Cricut project.
The first two are a plain format change. The third is not: a JPG has no transparent pixels, so no converter can "keep" a transparency that was never there. It has to be made, by clearing the background colour. This page does both, and keeps them apart so you always know which one you got.
What we measured
We converted test JPGs in Chrome 154 on 13 October 2026, read every PNG back with an independent decoder (Pillow) and compared it with the same JPG decoded by Pillow. For comparison we also saved the same pictures the way many online converters do it, by drawing the JPG on a browser canvas and saving that as PNG.
| Test file | JPG | This converter | Canvas "save as PNG" |
|---|---|---|---|
| Phone photo, 2048 × 1536, Display P3 colour profile, stored sideways | 1.31 MB | 5.80 MB, RGB, profile kept, upright | 7.58 MB, RGBA with an unused transparency channel, no profile |
| Grayscale signature scan, 300 DPI | 29 KB | 87 KB, grayscale, 300 DPI kept | 174 KB, full colour channels, no DPI |
| Flat graphic, 1600 × 1200 | 34 KB | 9 KB | — |
Pixel for pixel, our PNG of the phone photo matched the Pillow decode of the JPG exactly (largest difference 0 out of 255), and the tool checks the same thing in your browser for every file it writes. The size column is the honest part: our photo grew 4.4 times as a PNG, because PNG cannot use the lossy tricks that make JPG small. A screenshot, chart or logo with large flat areas is different, and can come out smaller than the JPG.
Three details most converters drop
The print size. A scan saved at 300 DPI carries that number in the file. Redrawing the picture on a canvas throws it away, and the PNG then prints at 72 or 96 DPI: a 708-pixel-wide signature meant to be 2.36 inches wide comes out three or four times larger. Here the DPI is written into the PNG and each result shows the size it will print at.
The colours. Recent iPhones and many cameras save photos in Display P3, a wider colour range than standard sRGB, and say so in an embedded profile. Without that profile, apps show the photo in sRGB and the most saturated reds and greens look duller. The profile is copied into the PNG unchanged.
Grayscale. A black-and-white scan has one channel. Written as a colour PNG it stores the same value three times, or four with an empty alpha channel. This converter keeps it as a grayscale PNG, which was half the size of the canvas version in our test.
Making the background transparent
Choose Make a plain background transparent when the picture sits on white or another single colour, as logos, signatures, icons and clip art usually do. The converter takes the colour from the edges of the image, clears everything connected to it, and turns the soft outline into partly see-through pixels instead of leaving a pale fringe. On our test logo it cleared 73% of the picture and kept every letter solid. The second option also clears enclosed areas, such as the inside of an O.
If less than 90% of the edge is one colour, the picture is most likely a photo, and the converter leaves the background alone and says why. Cutting a person or a product out of a photo is a different job. For fine control over the colour and tolerance, with a live preview, use Make background transparent.
What is not copied
The PNG gets the pixels, the DPI and the colour profile. It does not get the photo's EXIF details: the date, the camera model and, on phone photos, the GPS location. That is usually what you want when the file is going to someone else; if you need those details, keep the original JPG. A photo that was saved sideways with a "rotate when shown" note is turned upright in the pixels, because PNG has no such note and some apps would otherwise show it lying down.
Going the other direction, PNG to JPG makes a small file for sharing, and Convert image format handles WebP, AVIF and the rest. If the picture is already a PNG with a white box behind it, a guide on why some PNGs aren't really transparent explains what happened.