JPEG vs PNG vs WebP — Which Image Format Should You Use?

Choosing the wrong image format is one of the most common and costly mistakes in web development. A photograph saved as PNG can be ten times larger than the same image saved as JPEG. A logo saved as JPEG will have ugly compression artifacts around the edges. Understanding when to use each format is a fundamental skill for anyone who works with images.

JPEG: The Web Standard for Photographs

JPEG (Joint Photographic Experts Group) has been the dominant format for photographs since the 1990s. It uses lossy compression that works by discarding fine detail that the human eye is unlikely to notice — particularly in areas of gradual colour variation like sky and skin tones.

When to use JPEG

• Photographs: portrait, landscape, product, food, travel
• Hero images and banners with photographic content
• Any image with smooth colour gradients
• When maximum compatibility with old software is required

When not to use JPEG

• Images with text overlay — JPEG creates blurry halos around sharp edges
• Screenshots of user interfaces — the flat colours and sharp lines compress poorly
• Logos and icons — use SVG or PNG instead
• Images that need transparency — JPEG has no alpha channel

PNG: Lossless Quality with Transparency

PNG (Portable Network Graphics) was designed as an improved, patent-free replacement for GIF. It uses lossless compression, meaning every pixel is preserved exactly. PNG also supports a full alpha channel, allowing smooth transparency with 256 levels of opacity.

When to use PNG

• Logos, icons, and illustrations with transparency
• Screenshots and screen recordings
• Images with text overlaid on flat or simple backgrounds
• Graphics with sharp edges, hard lines, or solid colour areas
• Images that will be edited further (preserving full quality for next round of edits)

When not to use PNG

• Photographs — the file sizes are enormous compared to JPEG or WebP
• Any situation where file size is a priority

WebP: The Modern All-Rounder

WebP was developed by Google and released in 2010. It supports both lossy and lossless compression, as well as transparency and animation. In practice, WebP delivers roughly 25–35% smaller file sizes than JPEG at equivalent visual quality, and 20–30% smaller than PNG in lossless mode.

When to use WebP

• Web images in general — it is the best default choice for all new web projects
• When you need both lossy compression and transparency (WebP handles both)
• When you want smaller files than JPEG without visible quality loss
• Animated images — WebP animations are much smaller than equivalent GIFs

WebP browser support

WebP is supported by all modern browsers: Chrome, Firefox, Safari (since iOS 14 / macOS Big Sur), Edge, and Opera. The only concern is compatibility with very old software — some older image editing applications and email clients do not render WebP correctly.

Quick Decision Guide

• Photo for a website → WebP (or JPEG for maximum compatibility)
• Logo or icon with transparent background → PNG (or SVG if vector)
• Screenshot → PNG
• Animated image → WebP or GIF (WebP will be much smaller)
• Email attachment → JPEG or PNG (avoid WebP — email clients often don't support it)
• Social media upload → JPEG or PNG (check platform-specific requirements)
• Image needs to be edited further → PNG or TIFF (lossless source)

What About AVIF and HEIC?

AVIF (AV1 Image File Format) is a newer format that achieves even better compression than WebP — typically 30–50% smaller than JPEG at the same quality. It supports HDR, wide colour gamuts, and transparency. Browser support is now good (Chrome, Firefox, and Safari all support it) but encoding is slower than WebP.

HEIC (High Efficiency Image Container) is Apple's default format for iPhone photos. It produces smaller files than JPEG but is not widely supported outside Apple's ecosystem, making it unsuitable for general web use without conversion.

Summary Table

• JPEG: Photos, universal compatibility, no transparency, lossy only
• PNG: Graphics, transparency, screenshots, lossless, large file sizes for photos
• WebP: Best all-rounder for web, lossy + lossless + transparency, excellent browser support
• AVIF: Smallest files, best quality-to-size, good browser support, slower encoding

For most modern web projects, WebP is the best default. Use JPEG as a fallback for older software and JPEG-required platforms. Use PNG specifically when you need lossless quality or transparency on a platform that doesn't support WebP.