A Developer's Guide to the Best Image Formats for the Web

Format Comparison at a Glance

The table below summarizes the key characteristics of each format. Use this as a quick reference when deciding which format to use for a specific image.

Browser support percentages are based on global usage data from Can I Use. The highlighted formats (WebP and AVIF) offer the best compression for web use.

JPEG/JPG: The Universal Standard

JPEG (Joint Photographic Experts Group) has been the default image format for photographs since the early 1990s. It works everywhere, renders immediately, and compresses photographs effectively. Every browser, device, and image viewer supports JPEG without exception.

When to Use JPEG

JPEG remains a solid choice when you need maximum compatibility. Use JPEG as a fallback format in <picture> elements, or when you are serving images to users on older browsers or devices. JPEG is also appropriate when you are working with legacy systems that do not support modern formats.

When to Avoid JPEG

Do not use JPEG for images with sharp edges, text, or flat colors. The lossy compression algorithm creates visible artifacts around high-contrast edges. For logos, screenshots, or graphics with transparency, use PNG or SVG instead. For web delivery where file size matters, consider converting to WebP or AVIF.

Convert other formats to JPEG: PNG to JPG, HEIC to JPG, WebP to JPG.

PNG: Lossless Quality and Transparency

PNG (Portable Network Graphics) was designed as a patent-free replacement for GIF. It uses lossless compression, meaning no quality is lost during compression. PNG also supports full alpha transparency, allowing images to have smooth, semi-transparent edges.

When to Use PNG

PNG is the right choice for graphics that require transparency, such as logos placed over varying backgrounds. It also works well for screenshots, diagrams, and images with text where you need pixel-perfect clarity. The lossless nature means you can edit and re-save without degradation.

When to Avoid PNG

Do not use PNG for photographs. A 1920x1080 photograph might be 500 KB as a JPEG but 5 MB as a PNG. The lossless compression simply cannot compete with lossy formats for photographic content. For web delivery of transparent images, WebP often provides the same transparency with 30-50% smaller file sizes.

Convert to PNG: JPG to PNG, HEIC to PNG.

WebP: The Versatile Modern Format

WebP was developed by Google and released in 2010 as a modern replacement for JPEG, PNG, and GIF. It supports both lossy and lossless compression, transparency, and animation in a single format. With 97% global browser support, WebP is now a practical choice for most web projects.

When to Use WebP

WebP is an excellent default choice for web images. It typically produces files 25-35% smaller than JPEG at equivalent quality, and 30-50% smaller than PNG for graphics with transparency. Use WebP when you need a balance of quality, file size, and broad compatibility.

WebP vs JPEG

For photographic content, WebP consistently outperforms JPEG. In direct comparisons, WebP files are typically 25-35% smaller at the same visual quality. The difference is particularly noticeable at lower quality settings, where WebP produces fewer artifacts. Learn more in our detailed JPEG vs WebP comparison.

Convert to WebP: JPG to WebP, PNG to WebP, HEIC to WebP.

AVIF: Maximum Compression for Modern Browsers

AVIF (AV1 Image File Format) is the newest format in this guide, based on the AV1 video codec. It offers the best compression efficiency of any widely-supported format, producing files 40-60% smaller than JPEG at equivalent quality. Browser support has grown rapidly since 2020.

When to Use AVIF

AVIF is the best choice for photographs when you need the smallest possible file sizes. It excels at hero images, product photographs, and any content where every kilobyte impacts page load time. Use AVIF as the primary format in a <picture> element with WebP and JPEG fallbacks.

AVIF vs WebP vs JPEG

In head-to-head comparisons, AVIF files are typically 20-50% smaller than WebP and 40-60% smaller than JPEG at the same visual quality. The difference is most pronounced with photographic content containing fine detail and gradients. For simple graphics, the advantage is less dramatic.

Convert to AVIF: JPG to AVIF, PNG to AVIF, HEIC to AVIF.

SVG: Scalable Graphics for Icons and Logos

SVG (Scalable Vector Graphics) is fundamentally different from the other formats. Instead of storing pixels, SVG stores mathematical descriptions of shapes. This means SVG images scale to any size without quality loss, making them ideal for logos, icons, and diagrams.

When to Use SVG

Use SVG for any graphics that can be represented as shapes rather than pixels: logos, icons, diagrams, charts, and illustrations. A single SVG file can display at any resolution on any screen, from mobile phones to 4K monitors, without loss of quality. SVG files are also typically smaller than equivalent PNG files for simple graphics.

When to Avoid SVG

SVG cannot represent photographs or images with continuous tones. Converting a photograph to SVG would require describing millions of individual pixels as shapes, resulting in enormous file sizes. For photographic content, use raster formats like AVIF, WebP, or JPEG.

Convert SVG to raster formats when needed: SVG to PNG.

GIF: Legacy Animation Format

GIF (Graphics Interchange Format) dates back to 1987 and remains popular for short animations despite significant technical limitations. It supports only 256 colors per frame and uses lossless compression that is inefficient by modern standards.

When to Use GIF

The only practical reason to use GIF in 2026 is for compatibility with systems that do not support WebP or video formats. Some messaging platforms and content management systems still expect GIF for animated content. For new projects, WebP animation or video formats are preferable.

Better Alternatives to GIF

For animated content on the web, WebP animation offers the same browser-native experience with 80-90% smaller file sizes. For longer animations, consider using MP4 or WebM video with the autoplay muted loop playsinline attributes to create a GIF-like experience. Learn more about converting GIF to WebP.

HEIC: Convert Before Publishing

HEIC (High Efficiency Image Container) is Apple's default image format for iPhones and iPads. It offers excellent compression, but web browser support is limited to Safari. HEIC images must be converted before use on the web.

Why HEIC Is Not Web-Ready

Chrome, Firefox, and Edge do not support HEIC because the underlying HEVC codec requires patent licensing. While HEIC offers compression comparable to WebP, the lack of cross-browser support makes it unsuitable for web use. Users on non-Safari browsers will see broken images.

Converting HEIC for Web Use

Convert HEIC to web formats: HEIC to JPG, HEIC to WebP, HEIC to AVIF.

TIFF: Archive Format, Not for Web

TIFF (Tagged Image File Format) is a professional format used in print, archiving, and photography workflows. It supports lossless compression, multiple layers, and high bit depths. However, no major browser supports TIFF natively.

When You Encounter TIFF

TIFF files are common in professional contexts: scanned documents, print-ready artwork, medical imaging, and archival photography. If you receive TIFF files for web publication, they must be converted. The high quality of TIFF source files means you can convert to any web format without additional quality loss.

Convert TIFF for web use: TIFF to JPG, TIFF to PNG.

Format Decision Guide

Use this decision framework to choose the right format for any web image. Start by identifying your image type, then consider your compatibility requirements.

For Photographs and Complex Images

For Graphics with Transparency

For Animation

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

The Simpler Alternative: Smart Compression

If managing multiple formats and fallbacks feels like overkill for your project, there is a simpler path. Modern compression tools use intelligent algorithms that can make PNG and JPG files competitive with—or even smaller than—unoptimized WebP or AVIF.

A well-compressed JPEG or PNG with smart optimization can match or beat an unoptimized WebP in file size, while maintaining 100% browser compatibility. The format matters less than how well you compress it.

Why Smart Compression Works

Tools like Compress.FAST and TinyPNG use advanced algorithms that analyze each image individually. They identify optimal compression settings, remove unnecessary metadata, and apply intelligent quantization that preserves visual quality while dramatically reducing file size. The result is often a 60-80% reduction without visible quality loss.

When to Choose This Approach

Smart compression is the right choice when:

Try smart compression: Compress.FAST processes up to 1,000 images at once with intelligent optimization for each format.

Frequently Asked Questions