How to Convert PNG to JPG to Shrink File Size

PNG to JPG on DevOkk.com is that conversion in the browser. No account. Quality slider. The PNG never needs to visit a cloud queue so you can attach lunch to a Slack thread.

The PNG that should never have been a PNG

PNG is the right save for a logo, a UI capture with readable type, or anything with a hole. It is the wrong save for a noisy photograph. Phones and “high quality export” checkboxes produce photographic PNGs out of habit. Those files are huge because PNG is trying to describe every bit of sensor grain exactly.

JPEG is built for that grain. At 80–85 quality, the sandwich looks like the sandwich. The file lands in hundreds of kilobytes instead of megabytes. That is the convert worth doing.

A full-page screenshot of a documentation site is a gray area. If it is mostly a photograph-like hero plus some type, JPEG at a high quality can be acceptable. If it is a table of settings with 11-pixel labels, JPEG will fuzz the labels. Stay on PNG or recapture at a smaller size.

Transparency is a one-way door

The moment you need the pixels behind the subject to stay empty, stop. JPEG will fill the emptiness. A PNG mark on a transparent field becomes a mark on a rectangle. You will not get the field back by converting to PNG later. That second convert only wraps the rectangle in a new container.

If you are unsure whether the PNG has alpha, drop it on a dark desktop background in any viewer. Checkerboard or the desktop showing through means stay on PNG (and compress dimensions if you must, not the codec).

Screenshots versus “Save as PNG” photos

A clean capture of a dialog - gray panels, 13px labels, a checkbox - should stay PNG. JPEG ringing on a Cancel button is how a bug report looks unprofessional.

A PNG that is a photograph in all but extension is the opposite: trees, food, a face, a storefront. Those compress well as JPEG. The giveaway is file size plus visual noise. If the PNG is 7 MB and looks like a camera, convert. If the PNG is 180 KB and looks like a UI, leave it.

Phone screenshots of other photos (you photographed a monitor) are photographs. Treat them as JPG candidates. Phone screenshots of Settings are UI. Treat them as PNG.

Convert, then make it fit the slot

Open PNG to JPG, add the file, start near 85. Download. Open the JPEG at 100%. Look at skin, sky, and any type that was in the PNG. If the type is trash, you picked the wrong candidate - go back to PNG. If the photo is fine and Gmail still refuses the attachment, run the JPEG through the compressor and cap the width to something a phone column can use.

Do not PNG → JPG on site A, then JPG → “optimize” on site B, then upload to the CMS which re-encodes again. One local convert, one local resize if needed, then the real destination.

A “transparent” PNG that is actually a photo on a white studio sweep is still a photograph. The white is pixels, not a hole. JPEG is fine. Check by putting the file on a dark background; if you cannot see the desktop through it, there is no alpha to protect.

What this will not fix

It will not make a tiny logo look better. It will make it look dirtier.

It will not recover a PNG that was already a bad export (double-compressed, stretched). Garbage in, slightly smaller garbage out.

It will not batch a folder of SKUs. One file in a tab. A catalog pipeline is a different product.

Metadata can survive. If the PNG was a phone photo, GPS might still be in the JPEG. Conversion is not redaction.

When the PNG is a photo in all but name, and you do not need a hole, use PNG to JPG. If you later need a work file from a JPEG, that is the other direction, with no miracles attached. For the web budget after you have JPEG, use the compression guide.