Guide
There is no single best format for every website image. The right choice depends on the image content and browser support.
01
JPG remains a dependable choice for photographs and broad compatibility. WebP often produces a smaller delivery file at comparable visual quality and is well suited to modern browsers. Resize each photo close to its largest rendered dimensions and use responsive image variants rather than sending the same oversized file to every screen.
02
PNG is dependable for screenshots, interface graphics, and transparency. WebP can also preserve transparency and may reduce size. For simple logos and icons, SVG is often better because it stays sharp at any scale and is editable as vectors—but SVG is not a replacement for complex photographic imagery.
03
The largest visible image often has the biggest effect on perceived loading. Avoid lazy-loading the main hero image, provide explicit width and height to prevent layout shifts, and compress it carefully. Images farther down the page can usually be lazy-loaded so they do not compete with critical content.
04
A single site may correctly use several formats: WebP or JPG for product photos, PNG for a screenshot, and SVG for a logo. Test representative images because the best result depends on texture, transparency, sharp edges, and the audience's browsers—not only the file extension.
05
Keep the master file, crop to the intended composition, resize to realistic display dimensions, choose a content-appropriate format, and compare quality before publishing. Add meaningful alt text when the image conveys information. Finally, test the actual page on mobile and a slower connection instead of judging the file in isolation.