JPG vs PNG vs WebP — Which Format Is Best for Websites?

Updated: 2025-10-09

Choosing the right image format isn’t always obvious. JPEG, PNG, WebP and AVIF each offer different trade‑offs between quality, transparency support, file size and browser support. This guide explains when to use each format and how to combine them for maximum performance.

JPEG (JPG)

JPEG is the most widely supported lossy format and excels at compressing photographs and complex gradients. It uses lossy compression to discard data your eyes are unlikely to notice. At quality settings around 70–85, JPEG files remain sharp while being substantially smaller than raw photos. However, JPEG does not support transparency and may produce artifacts around sharp edges.

PNG

PNG is a lossless format designed for graphics, icons and images requiring transparency. It preserves every pixel and supports a full alpha channel. Because it doesn’t discard information, PNG files are typically larger than JPEGs for photos but smaller for flat artwork. Use PNG for logos, text overlays, UI screenshots and any content where crisp edges matter.

WebP

Developed by Google, WebP offers both lossy and lossless modes and supports transparency. WebP images are typically 25–35 % smaller than equivalent JPEG or PNG files【413330301302362†L220-L234】. Most modern browsers support WebP, but older versions of Safari and some email clients do not. When possible, serve WebP as the default with a JPEG or PNG fallback.

AVIF

AVIF is a next‑generation format based on the AV1 video codec. It produces even smaller files than WebP but is currently supported by fewer browsers. If your audience uses the latest versions of Chromium or Firefox, consider serving AVIF alongside WebP and JPEG.

How to choose

Use JPEG for photographs where transparency isn’t needed, PNG for graphics and images with transparency, WebP for most web images when browser support is available, and AVIF where cutting‑edge support exists. In practice, you can serve multiple formats using the <picture> element:

<picture>
  <source srcset="image.avif" type="image/avif" />
  <source srcset="image.webp" type="image/webp" />
  <img src="image.jpg" alt="Description of image" />
</picture>
        

The browser will choose the first format it supports, falling back to JPEG. This approach provides maximum compatibility while taking advantage of next‑gen formats.

Conclusion

There is no single “best” image format—each serves a purpose. For most websites, the optimal strategy is to generate multiple encodings and let browsers select the best one. When combined with proper resizing and compression, format choice has a huge impact on performance and user experience. Use tools like SqueezeJPG to experiment with different formats and find the right balance of quality and size for your content.