PNG vs JPG: Which Format Should You Use?

Every image you publish forces a quiet decision: PNG or JPG? Most people decide by habit — whatever their screenshot tool or camera produces. But the two formats were engineered for opposite jobs, and using the wrong one either bloats your pages or smudges your graphics. This guide explains the difference once and for all, with the practical numbers that matter.

Two formats, two compression philosophies

JPG (or JPEG, for Joint Photographic Experts Group) uses lossy compression. It divides the image into small blocks and discards visual information your eye is bad at noticing — subtle colour shifts, high-frequency detail in busy areas. The result: photographic images shrink to a tenth of their raw size or less while still looking natural. The cost: the discarded detail is gone forever, and each re-save discards a little more.

PNG (Portable Network Graphics) uses lossless compression, closer to how a ZIP file works. Every single pixel survives exactly. Flat areas of identical colour compress beautifully; noisy photographic detail barely compresses at all. PNG also supports an alpha channel — real transparency, from fully invisible to any degree of translucency.

What this means in practice

The philosophical difference produces very predictable real-world behaviour:

Where JPG wins

Photographs are JPG territory. A sunset, a portrait, a product shot — these images are full of gradual colour transitions and fine noise, exactly what JPG's compression model was designed for. At quality 85, a typical photo keeps 95%+ of its visual fidelity at a fraction of the weight. That matters everywhere files travel: web pages load faster (and page speed is a ranking factor), email attachments fit under size caps, and phone storage lasts longer.

JPG is also the universal format. Every browser, device, CMS, marketplace and photo printer on earth accepts it. When in doubt about compatibility, JPG is never wrong.

Where PNG wins

PNG dominates wherever precision matters more than weight:

• Logos and icons — sharp edges stay sharp, and transparency lets the graphic sit on any background.
• Screenshots — interface text stays crisp. JPG-compressed screenshots grow fuzzy "halos" around letters, because text is exactly the high-frequency detail JPG throws away.
• Charts, diagrams and line art — flat colours compress losslessly to tiny files; JPG both enlarges and smears them.
• Images you will edit again — as a lossless master copy, PNG survives unlimited open-edit-save cycles.

The two-second rule

Ask one question: is it a photo?

• Photo → JPG. Quality 85 for general use, 92 when detail is critical.
• Not a photo (logo, screenshot, text, chart, anything transparent) → PNG.

That single rule gets the right answer more than 95% of the time. The main exception: a screenshot that is mostly a photograph (for instance a full-screen video frame) — treat it as a photo.

Converting between the two

Converting PNG → JPG is routine and safe when the content is photographic: you trade invisible detail for a much smaller file. Two things to know before you convert:

1. Transparency is flattened. JPG has no alpha channel, so transparent regions must become a solid colour — our PNG to JPG converter flattens onto clean white, the standard choice.
2. Keep the original. Conversion is one-way: you can convert the JPG back to a PNG container later, but the discarded detail never returns. Archive the PNG master if you may need to edit again.

Converting JPG → PNG is rarely useful. It makes the file several times bigger without restoring any quality — the loss already happened. Do it only when a system strictly requires PNG input.

What about WebP and AVIF?

Modern formats like WebP and AVIF compress photos better than JPG and support transparency like PNG — they are excellent choices for websites you control. JPG and PNG still matter because they are the universal interchange formats: the files you send to clients, upload to marketplaces, or archive for the long term. For the full landscape, see our guide to every image format that matters in 2026.

The bottom line

PNG and JPG are not competitors — they are specialists. JPG carries your photographs efficiently; PNG preserves your graphics exactly. Learn the two-second rule, keep lossless masters of anything you might edit, and convert deliberately rather than by accident. Your pages will be faster and your graphics sharper for it.