JPG vs PNG vs WEBP

When you save an image, the format bar offers three familiar names: JPG, PNG, and WEBP. They look like interchangeable options, but each one was designed for a different job, and picking the wrong one costs you either visible quality or unnecessary file size. This article compares the three formats directly on the points that actually matter: compression behavior, transparency, support, and what each does to photographs and graphics.

What each format was built for

JPG is the veteran of the group, designed in the early 1990s for photographic images that need to be small. PNG arrived a few years later with the opposite goal: lossless reproduction of graphics with clean edges and transparent backgrounds. WEBP is the modern challenger from Google, built to offer both a lossy mode and a lossless mode in a single format while producing smaller files than the older two.

• JPG: lossy photo format, no transparency, maximum compatibility.
• PNG: lossless graphics format, full transparency, larger files for photos.
• WEBP: lossy and lossless modes, transparency, animation support, smaller files.

How compression differs

The core difference is what happens to the pixels when you save. JPG applies lossy compression that removes fine detail the eye is unlikely to notice, which is why a photo that starts at several megabytes of raw data can drop to under a megabyte. Push JPG quality low enough and you will see the classic symptoms: blocky patches in smooth gradients, ringing around sharp edges, and smeared text.

PNG is lossless, so it stores every pixel exactly and the image never degrades when you re-save it. The cost is that photographs with natural gradients compress poorly and stay large. WEBP offers both paths: its lossy mode targets the same quality as JPG at a noticeably smaller file, commonly reported as a reduction of roughly a quarter to a third in typical photo tests, and its lossless mode competes with PNG. Because the lossy side of WEBP is more efficient than JPG at the same quality level, you can often lower the size further without making the image look worse.

The distinction also explains why re-saving matters. Every time a lossy JPG is edited and saved again, a new round of compression is applied on top of the damage from the last one, and the artifacts accumulate until the image looks soft and patchy. PNG and lossless WEBP never have this problem, because they preserve the pixels exactly and only the final lossy export, if there is one, costs anything. If you expect to edit an image more than once, keep an editable lossless master and only export the lossy JPG or WEBP at the very end.

Transparency and edges

If your image needs a see-through background, JPG cannot do it at all. Every pixel in a JPG is opaque, so a "transparent JPG" does not exist; saving a transparent image as JPG fills the background with white or black. PNG introduced full alpha transparency, including partial transparency for smooth antialiased edges, which is why it is the standard for logos and cut-out product shots. WEBP also supports full alpha transparency in both its lossy and lossless modes, so it can replace PNG for transparent graphics wherever the target accepts it.

For sharp-edged content such as text, icons, screenshots, and charts, the lossy smearing of JPG is actively harmful, which is another reason graphics belong in PNG or WEBP. Text saved as a low-quality JPG develops halos that make it look blurry even at small sizes.

File size in practice

The numbers vary with content, but the pattern is consistent:

• A photograph saved as PNG is often two to five times larger than the same photo as a high-quality JPG, with no visible benefit for most photos.
• A photograph as lossy WEBP is typically smaller than the same photo as a quality-matched JPG.
• A screenshot or logo saved as JPG is smaller than its PNG version, but the compression degrades text, so the saving is not worth it.
• Lossless WEBP is usually smaller than PNG for the same graphic content, which helps when a site needs transparency without the PNG weight.

If you are curious about your own files, the honest test is to save one image in all three formats at a few quality levels and compare both the appearance and the byte sizes.

Where each format works

Compatibility used to be the deciding factor, and it still matters for specific audiences. JPG and PNG open everywhere, including printers, old software, and email clients. WEBP had a slow start on the web, but Safari added support in 2020, and since then Chrome, Firefox, Edge, and every major operating system handle it normally. Social platforms, image hosts, and content management systems now accept WEBP uploads in the vast majority of cases. The remaining exceptions are niche: very old software, some print workflows, and a handful of specialized devices.

The practical verdict

• Choose WEBP for images going on a website or blog: smaller files, faster pages, and transparency when needed.
• Choose JPG for photos being emailed, printed, or sent to someone whose software you cannot control.
• Choose PNG for screenshots, logos, charts, and any image that needs a transparent background on a platform that does not accept WEBP.
• Keep a lossless original of anything you may edit again, and only export the compressed copies at the end.

Converting and testing your own files

The best way to settle a format argument is to test it on your own content rather than trusting generic advice. Because all processing can happen locally, you can convert the same image to JPG, PNG, and WEBP side by side and compare sizes directly. An image converter does this conversion in the browser without uploading your files, and an image compressor shows the before-and-after savings as you adjust quality. If the goal is a specific destination size, such as a 1280 by 720 thumbnail or a 1080 by 1080 post, resize first with the image resizer and then export in the format that destination accepts.

The short summary is easy to remember: photographs want JPG or lossy WEBP, graphics and transparency want PNG or lossless WEBP, and compatibility is the only good reason to avoid WEBP. Match the format to the content and you will rarely need to think about it again.