PNG vs JPG vs WebP: which image format should you use?

Pick the wrong image format and you either ship a blurry photo or a needlessly huge file that slows your page down. The choice comes down to three formats — JPG, PNG and WebP — and a couple of simple questions about what’s in the image.

JPG: for photographs

JPG (or JPEG) uses lossy compression: it throws away detail your eye is unlikely to notice in exchange for much smaller files. That’s exactly right for photographs and other images with smooth gradients and many colours, where the discarded detail is invisible. It’s the wrong choice for anything with sharp edges or text, where the compression leaves visible fuzz (“artefacts”), and it can’t store transparency.

PNG: for graphics, text and transparency

PNG uses lossless compression — it reproduces every pixel exactly — and supports transparent backgrounds. That makes it ideal for logos, icons, screenshots, diagrams and any image with crisp lines or text. The catch is file size: a photograph saved as PNG is typically several times larger than the same photo as JPG, with no visible benefit. Reach for PNG when you need perfect edges or transparency, not for photos.

WebP: the modern all-rounder

WebP is a newer format that does both jobs well: it offers lossy compression that beats JPG at similar quality, and a lossless mode with transparency like PNG — usually at smaller sizes than either. Every current browser supports it, so for web images it’s often the best default. The main reason to still export JPG or PNG is compatibility with older software or a platform that specifically asks for them.

A quick decision guide

• Photograph for the web → WebP, or JPG for maximum compatibility.
• Logo, icon, screenshot or anything with text → PNG, or lossless WebP.
• Needs a transparent background → PNG or WebP (never JPG).
• Smallest possible file at good quality → WebP.

Size matters more than format

Whichever format you choose, the biggest win is usually not the format itself but the dimensions and compression level. A photo that displays at 800 pixels wide but was exported at 4000 pixels is wasting most of its bytes. Resize it to the size it’s actually shown at with the Image Resizer, then run it through the Image Compressor to find the quality sweet spot — the live size readout lets you shrink the file until just before quality visibly drops.

Embedding tiny images

For very small assets like a single icon, you can skip the separate file entirely and inline the image as a Base64 data URI, saving a network request. Keep this for small images only — Base64 adds about a third to the size, so it’s counterproductive for anything large.

Get the format and the size right and your images will look sharp while loading fast — and since all of these tools run in your browser, your images never leave your device.