How much smaller will the JPG be?

Usually dramatically smaller for photographic content. On the fixed test image used here, a 3.97 MB PNG became a 375 KB JPG — a reduction of about 91%. Screenshots and flat-colour graphics save far less, and can occasionally grow, because those are exactly the images PNG handles well and JPG handles badly.

What happens to transparency?

It is lost. JPG has no alpha channel at all, so transparent areas are filled — with white here. If your PNG has a transparent background and you need to keep it, convert to WebP instead, which supports both transparency and strong compression.

Will converting to JPG lose quality?

Yes. JPG is lossy by design, and this is a one-way conversion. At the default quality of 82 the loss is invisible at normal viewing sizes for photographs. For screenshots and images containing text, JPG is a poor choice: it smears sharp edges in a way that is immediately noticeable.

Should I convert a screenshot to JPG?

Usually not. Screenshots are full of hard edges and text, which is precisely what JPG compression handles worst — you will see haloing around letters. Keep screenshots as PNG, or use WebP if you need them smaller.

Is my image uploaded?

No. Both the decode and the encode run in this browser tab. The Uploaded readout beside each result measures the page's own outbound network traffic, so a successful conversion reads 0 B.

Is there a file size limit?

None imposed. Upload caps exist because bandwidth and storage cost money; neither is involved here. Your device's memory is the only real ceiling.

Can I convert many PNGs at once?

Yes. Add as many as you like in one go — there is no queue because there is no server. Very large batches are limited only by memory.

Which quality setting should I choose?

82 for general use and email. 95 or above if the image will be printed or edited further. Below 60 you will begin to see softening in flat areas and haloing around edges.

Will there be a watermark?

No. Nothing is added to your image, and there is no paid tier.

My JPG came out bigger than the PNG. Why?

That happens with graphics rather than photographs — logos, diagrams, screenshots, anything with large areas of a single colour. PNG compresses flat colour extremely efficiently, while JPG spends bits describing edges that PNG stores almost for free.

Should I use JPG or WebP?

JPG for anything you hand to another person or print — it is universally supported. WebP for images on a site you control: on the same test image it produced a file about 40% smaller than the JPG, and it keeps transparency.

Does this remove metadata from the image?

Most metadata is not carried across. That is usually desirable when publishing, since it strips any location or device information that may be embedded.

Convert PNG to JPG

Much smaller files, made on your own machine. Nothing is uploaded, there's no size limit, and no account is needed.

ReadyPNG → JPG

Uploaded0 B

What next

How do I convert PNG to JPG?

To convert a PNG to JPG, drop the file onto this page and download the JPG it returns. The conversion runs in your browser, so nothing is uploaded and there is no size limit. Expect a dramatic size reduction — on our test image a 3.97 MB PNG became a 375 KB JPG. Transparent areas become white.

How to do it

Open the converter. Open this page in any modern browser. Nothing to install, no account to create.
Add your PNG files. Drag them onto the panel or click to choose. Add as many as you like — there is no upload and therefore no queue.
Pick a quality. 82 is the default and suits most uses. Lower it to fit an upload limit; raise it toward 95 if the image will be printed.
Download the JPG. Each result carries its own download link and a Smaller by readout showing exactly how much was saved.

At a glance

Converts	PNG to JPG
Transparency	Not supported by JPG — transparent areas become white
Compression	Lossy — quality is adjustable, default 82
Where it runs	In this browser tab. The file is not uploaded
File size limit	None imposed — your device memory is the ceiling
Cost	Free
Account needed	No
Watermark	None
Works offline	Usually after first use, but not guaranteed — there is no offline app

What it actually produces

Measured, not estimated. A procedurally generated 2400×1600 (3.8 MP) test image built to carry photographic entropy: value noise across nine octaves down to near-pixel scale, a dense field of small high-contrast features, a smooth gradient, hard edges and light grain. It is not a photograph — it is reproducible, which a photograph is not. Each figure below comes from running that image through this page.

Input	Output	Change
3.97 MB	375 KB	91% smaller

Your own files will differ — a photograph, a screenshot and a diagram compress very differently. The point of a fixed image is that the formats can be compared with each other, not that your result will match.

How much smaller does JPG make a PNG?

For photographs, a great deal smaller. On the fixed test image used for every measurement on this site, a 3.97 MB PNG became a 375 KB JPG — a reduction of about 91%.

That gap is the whole reason the conversion exists. PNG stores every pixel exactly; JPG discards the detail your eye is least likely to miss. For a photograph, that trade is overwhelmingly worth it.

For a screenshot or a diagram, it is not. Read on.

Why did my transparent background turn white?

Because JPG has no way to store transparency. The format has no alpha channel — it never had one, and it never will.

When a PNG with a transparent background is converted, something has to be put behind it. This converter fills it with white, which is the conventional choice and the right one for most documents.

If you need the transparency, convert to WebP instead. WebP supports an alpha channel and compresses close to JPG, which makes it the correct destination for a transparent image that needs to be smaller.

When is JPG the wrong target?

Screenshots, diagrams, logos, and anything containing text.

JPG’s compression works by discarding high-frequency detail — and a hard black edge against white is high-frequency detail. The result is visible haloing around letters and lines, an artefact that is obvious at a glance and impossible to remove afterwards.

Those images are exactly the ones PNG was designed for. If a screenshot is too large, the right fix is to optimise the PNG losslessly or convert it to WebP, not to make it a JPG.

You may even find the JPG comes out larger: PNG compresses large areas of flat colour almost for free, while JPG has to spend bits describing every edge inside them.

Which quality setting?

Email, web forms, general sharing — the default of 82. Small, and indistinguishable from the source on screen.
Printing or further editing — 95 or above.
Fitting under an upload cap — drop toward 60 and watch the Smaller by readout until it fits.

Each change re-encodes from your original file rather than from the previous result, so you can move the slider freely without compounding the loss.

Questions

How much smaller will the JPG be?: Usually dramatically smaller for photographic content. On the fixed test image used here, a 3.97 MB PNG became a 375 KB JPG — a reduction of about 91%. Screenshots and flat-colour graphics save far less, and can occasionally grow, because those are exactly the images PNG handles well and JPG handles badly.
What happens to transparency?: It is lost. JPG has no alpha channel at all, so transparent areas are filled — with white here. If your PNG has a transparent background and you need to keep it, convert to WebP instead, which supports both transparency and strong compression.
Will converting to JPG lose quality?: Yes. JPG is lossy by design, and this is a one-way conversion. At the default quality of 82 the loss is invisible at normal viewing sizes for photographs. For screenshots and images containing text, JPG is a poor choice: it smears sharp edges in a way that is immediately noticeable.
Should I convert a screenshot to JPG?: Usually not. Screenshots are full of hard edges and text, which is precisely what JPG compression handles worst — you will see haloing around letters. Keep screenshots as PNG, or use WebP if you need them smaller.
Is my image uploaded?: No. Both the decode and the encode run in this browser tab. The Uploaded readout beside each result measures the page's own outbound network traffic, so a successful conversion reads 0 B.
Is there a file size limit?: None imposed. Upload caps exist because bandwidth and storage cost money; neither is involved here. Your device's memory is the only real ceiling.
Can I convert many PNGs at once?: Yes. Add as many as you like in one go — there is no queue because there is no server. Very large batches are limited only by memory.
Which quality setting should I choose?: 82 for general use and email. 95 or above if the image will be printed or edited further. Below 60 you will begin to see softening in flat areas and haloing around edges.
Will there be a watermark?: No. Nothing is added to your image, and there is no paid tier.
My JPG came out bigger than the PNG. Why?: That happens with graphics rather than photographs — logos, diagrams, screenshots, anything with large areas of a single colour. PNG compresses flat colour extremely efficiently, while JPG spends bits describing edges that PNG stores almost for free.
Should I use JPG or WebP?: JPG for anything you hand to another person or print — it is universally supported. WebP for images on a site you control: on the same test image it produced a file about 40% smaller than the JPG, and it keeps transparency.
Does this remove metadata from the image?: Most metadata is not carried across. That is usually desirable when publishing, since it strips any location or device information that may be embedded.

About these formats

Sources

ITU-T T.81 — the JPEG specification — ITU-T
Portable Network Graphics (PNG) Specification, Third Edition — W3C
MozJPEG, the JPEG encoder used here — Mozilla