Convert PNG to JPG
Drop PNG files in and get JPGs out, with control over the one thing this conversion always has to decide: what color goes where the transparency used to be. A folder of screenshots converts as fast as your laptop can encode them and none of them are uploaded to anyone.
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Add to Chrome — freeDrop your PNG file here, or click to browse
Up to 50 MB. Deleted automatically after 30 minutes.
What it does
- Choose the color that replaces transparency
- Adjustable JPEG quality
- Convert and resize in one pass
- Batch conversion with ZIP download
- No watermark, no sign-up
How to use PNG to JPG
- 1
Pick the background color
If your PNG has transparent areas, choose what they become. White suits documents and screenshots; match your page color for web images.
- 2
Set the quality
92 percent is the default and is visually indistinguishable from the original for most images. Lower it if file size matters more.
- 3
Drop in your PNGs
Add one file or many. Each is converted independently and listed with its new size, so you can see how much each one saved.
- 4
Save the JPGs
Download files individually, or take the whole batch as a single ZIP.
How it works
The PNG is decoded to raw pixels. A canvas is created at the same dimensions and filled with your chosen background color. The decoded image is then drawn on top of that fill, and the canvas is encoded as JPEG at your chosen quality.
The order of those steps is the entire tool. Draw first and fill afterwards and you cover the image; skip the fill and every transparent pixel becomes transparent black, which is what produces the black background people report when a converter has not thought about it. Painting the background before the image is the only sequence that gives a predictable result.
Quality is passed through to the browser's own JPEG encoder. The number is not a percentage of anything measurable — it is a knob controlling how aggressively the frequency coefficients are quantized. What matters practically is that 100 is much larger than 95 for no visible gain, that the range from 95 down to about 80 is nearly indistinguishable on photographs, and that below roughly 60 the characteristic eight-by-eight blocking starts to appear on flat areas.
If you set a maximum width, the resize happens before encoding, using the same step-down approach as the resizer so that a large reduction does not come out aliased.
When you'd use this
The most common reason is a size limit. PNG screenshots are enormous — a full-screen capture routinely lands between one and three megabytes — and the same image as a JPEG is usually under two hundred kilobytes with no visible difference. Attaching one to a ticket, an email, or a form is where that matters.
The second is compatibility with something old or strict. Plenty of upload forms, print services, photo kiosks and older document systems accept only JPEG. This is less about capability than about a whitelist someone wrote years ago and has not revisited.
The third is stripping transparency deliberately. If a design needs a logo on a solid background and you keep having to composite it manually, converting once with the right background color chosen is simpler than doing it in every document.
What this cannot do
It cannot recover quality that the PNG never had, and it cannot make a JPEG smaller than the format allows for the detail present. A photograph of foliage will always be a larger file than a photograph of a clear sky at identical settings, because there is genuinely more information in it.
It also cannot preserve an animation. Animated PNG files convert to a single still frame — the first one — because JPEG has no concept of multiple frames.
Examples
A screenshot with no transparency
Screenshots are where this conversion pays off most dramatically. PNG stores every pixel exactly, which is wasteful for an image containing photographic gradients or antialiased text over a busy background. Note that a screenshot of flat-colored UI would show a much smaller saving.
A logo with a transparent background
The transparent area is now solid white, permanently. Placing this logo on a colored page will show a white rectangle around it. That is not a fault in the conversion — it is what JPEG is, and it is the single most common reason someone regrets converting a logo.
Frequently asked questions
Why did my transparent logo end up with a white box around it?
Because JPEG has no transparency channel. Every pixel must have a color, so the transparent region is filled before encoding — white by default here, and you can change it with the color picker. If you need the transparency, JPG is the wrong destination format entirely; keep the PNG or convert to WebP, which supports both transparency and small file sizes.
Will converting to JPG lose quality?
Yes, though usually not visibly at the default setting. JPEG is a lossy format: it discards detail your eye is least likely to notice in order to shrink the file. At 92 percent quality that loss is essentially invisible on photographs and screenshots. On images with sharp text or hard-edged flat color it shows up as faint haloing around the edges.
When is PNG actually the better format to keep?
Whenever the image has large areas of flat color, sharp edges, text, or transparency — logos, icons, diagrams, charts, and UI mockups. For those PNG is often both smaller and sharper than JPEG. The conversion is worth making for photographs, photographic screenshots, and anything with continuous tonal gradients.
Can I convert a whole folder at once?
Yes. Select or drop as many files as you like and each is converted separately with its own result line, then offered as one ZIP archive. The practical limit is your browser's memory rather than a rule in the tool, and a failure on one file does not stop the rest of the batch.
Does the JPG keep the PNG's metadata?
No. The image is decoded to raw pixels and re-encoded, so PNG text chunks, color profile data, and any embedded comments are not carried over. For most uses that is a benefit rather than a loss, since it strips anything identifying that a screenshot tool or editor may have written into the file.
Further reading
- We Re-Saved a JPEG Twenty Times and Nothing HappenedEveryone has heard that a JPEG gets worse every time you open and save it, and most people have seen the artwork made by re-saving an image five hundred times to prove it. So we measured it properly. Re-saving at the same quality, twenty times, changed the image by nothing at all — and then we found the conditions where it degrades badly.
- Interlacing a PNG Made It 27% Bigger and Did Not HelpPNG has an interlacing option that shows a rough version of the image while it loads, in the same spirit as progressive JPEG. Unlike progressive JPEG, it is reliably and substantially more expensive — and the preview it produces is worse. Here is what it cost on two very different images.
- JPEG Does Not Just Look Worse on Text — It Is Bigger TooThe usual advice is "JPEG for photos, PNG for graphics", and it is given as a quality argument: JPEG smears the edges of text and flat color. That is true, and it buries the more useful half. On the same image, at the same settings, the JPEG is also the bigger file — three times bigger on a page of text. You are not trading size for quality. You are losing both.