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PNG to JPG Converter - Convert PNG to JPG Free Online

Convert PNG to JPG in your browser with an adjustable quality setting. Batch conversion is supported, and no file is ever uploaded to a server.

What PNG to JPG Does

This tool decodes your PNG onto an in-browser canvas and re-encodes the raw pixel data with the browser's own JPG encoder. The two formats are built on opposite assumptions, and that difference is the whole story. PNG is lossless: every pixel value survives the round trip untouched, and the format carries an alpha channel, so pixels can be fully or partially transparent. JPG is lossy and has no alpha channel at all. Because of that, two things happen during conversion. First, every transparent or semi-transparent pixel has to be composited onto something opaque before encoding — this tool fills the canvas with white and draws your image on top, so a transparent background becomes a white background and a soft anti-aliased edge picks up a white fringe. Second, the JPG encoder deliberately discards visual information it judges to be less noticeable, mostly fine chroma detail and high-frequency texture. The Quality slider, which runs from 1 to 100 and defaults to 92, controls how aggressive that discarding is: higher values keep more detail and produce a larger file, lower values shrink the file and eventually leave visible ringing around sharp edges and text. What the conversion does not do is add information. It won't sharpen a soft image, it won't repair a low-resolution PNG, and it won't reduce the pixel dimensions — the output has exactly the same width and height as the input. It also can't preserve transparency in any form, and converting the result back to PNG later will not recover the detail the JPG encoder already threw away.

Why You'd Convert PNG to JPG

PNG is the wrong format for photographic content, and its file sizes show it. Switching to JPG usually cuts the size by most of its bulk with no visible difference on a photo.

Shrink a photo exported as PNG down to a fraction of its size before emailing or uploading it
Meet upload limits on forms, job portals, and marketplaces that cap files at a few megabytes
Satisfy systems that accept JPG only, such as older CMS platforms, print shops, and passport or ID upload tools
Flatten screenshots or product renders onto a clean white background in one step for catalog listings

How to Convert PNG to JPG

Four steps, all of them local — the image is decoded, re-encoded, and handed back without ever touching a server.

1

Drop in one PNG or a whole batch — every file in the run uses the same settings

2

Set the Quality slider; 92 is the default and works well for photos, while 75-85 gives noticeably smaller files

3

Apply the conversion — the button reads "Converting..." while the encoder works through your files

4

Download each JPG on its own, or grab the whole batch as a single ZIP

Frequently Asked Questions

Not in JPG — the format has no alpha channel, so transparency simply cannot be stored in it. This tool composites your image onto white before encoding, which is why the background comes out white rather than black or garbled. If transparency matters, convert to WebP instead, or keep the PNG. Converting the finished JPG back to PNG restores the alpha channel as a container but leaves every pixel opaque white where the transparency used to be.
Yes, some. JPG is a lossy format, so the encoder always discards a portion of the fine detail — that loss is how it achieves its file sizes. At the default quality of 92 the difference is very hard to see on a photograph. Flat graphics, screenshots, logos, and anything with sharp text or hard color edges suffer more visibly, because those are exactly the patterns JPG compression handles worst.
Start at the default of 92 for photos; it is generous enough that artifacts stay invisible in normal viewing. Drop to 75-85 when file size matters more than pixel-level fidelity, such as email attachments or bulk web uploads. Below about 60 you will start seeing blocky patches in smooth gradients and halos around edges. There is no single correct number — check one representative image at your chosen setting before running a large batch.
No. Decoding and re-encoding both happen in your browser through the canvas API, so the image data never leaves your device. That has two practical consequences: sensitive documents and personal photos stay private with no trust required, and the ceiling on batch size is your device's memory and CPU rather than an upload limit. Once the page has loaded, the tool keeps working offline.
Yes. Add as many PNG files as you like and they all run through the same Quality setting in one pass, then download individually or as a single ZIP. Because one quality value applies across the whole batch, mixed content can come out uneven — a detailed photo and a flat diagram respond very differently to the same number. Spot-check the busiest image in the set before trusting the rest.
For photographs, expect roughly 70-90% smaller at the default quality, because PNG stores photographic noise very inefficiently while JPG is designed around it. For flat graphics, screenshots, and line art the saving is much smaller, and occasionally the JPG comes out larger than the PNG — those images compress extremely well in PNG's lossless scheme. Exact numbers depend entirely on image content and the quality setting you pick.
You can, and the file will be a valid lossless PNG from that point forward, but it will not undo anything. The detail the JPG encoder discarded is gone permanently, and the white background that replaced your transparency stays white. Converting back is useful when you need a lossless base for further editing — it stops new artifacts accumulating — but it is not a way to recover the original PNG.
Yes. It runs on the same canvas API that mobile Safari, Chrome, and Firefox all support, so conversion works from a phone or tablet with no app to install. The limits are practical rather than technical: mobile devices have less memory, so very large PNG files or long batches may be slow or run out of room. Converting in smaller groups usually solves it.

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