How to Choose the Right Image Format for the Web
JPEG vs PNG vs WebP vs AVIF vs SVG — when to use each format, file size comparisons, and quality considerations.
- JPEG vs PNG vs WebP vs AVIF vs SVG — when to use each format, file size comparisons, and quality considerations.
- Image Format Overview.
- Choosing by Use Case.
- WebP and AVIF: Modern Formats.
- SVG for Icons and Illustrations.
Image Format Overview
Choosing the right image format is one of the biggest performance decisions in web design. The wrong format can make an image 3–10 times larger than necessary. Five formats matter on the modern web: JPEG for photographs, PNG for images needing transparency or pixel-perfect rendering, WebP as a modern replacement for both, AVIF with even better compression, and SVG for vector graphics. The fundamental divide is lossy formats (JPEG, WebP, AVIF) that discard visual data for smaller files, and lossless formats (PNG, lossless WebP, SVG) that preserve every pixel.
Choosing by Use Case
Match format to content. Photographs and complex images with many colors → JPEG or WebP. Screenshots, diagrams, and images with sharp text → PNG or lossless WebP. Images needing transparency → PNG, WebP, or AVIF. Icons, logos, and simple illustrations → SVG (scales to any size without quality loss). Animated images → use video (MP4) instead of GIF — it’s 80% smaller. If you can only support one modern format, choose WebP — it handles both lossy and lossless, supports transparency, and has universal browser support.
WebP and AVIF: Modern Formats
WebP provides 25–35% smaller files than JPEG at equivalent quality and supports transparency. AVIF goes further with 30–50% improvement over JPEG. Browser support for WebP is universal. AVIF support is nearly universal (Chrome 85+, Firefox 93+, Safari 16.4+). Use the picture element to serve modern formats with fallbacks. Use the Image Converter to batch-convert your images to optimal formats.
SVG for Icons and Illustrations
SVG is fundamentally different — it’s code, not pixels. An SVG icon at 2KB stays 2KB at any size, while PNG needs separate files for each resolution. Use SVG for any graphic made of shapes, lines, and text: logos, icons, illustrations, charts. Inline SVGs can be styled with CSS and animated with JavaScript. Optimize with SVGO to remove metadata and simplify paths — unoptimized SVGs from design tools can be 10x larger than necessary.