Image Format Guide: PNG, JPG, WebP, SVG — When to Use Each

Choosing the wrong image format wastes bandwidth, slows page loads, and degrades visual quality. Each format has specific strengths — photographs look best in one format, logos in another, and icons in yet another. This guide helps you make the right choice every time.

Quick Decision Chart

Format Deep Dive

JPEG (JPG)

The standard for photographs since 1992. Uses lossy compression based on the discrete cosine transform (DCT).

Best for: Photographs, natural scenes, complex images with gradients. Avoid for: Text, logos, screenshots, images with sharp edges.

Quality sweet spots:

• Quality 85: Visually lossless for most photos (best default)
• Quality 75: Good balance for web thumbnails
• Quality 95: Near-lossless for print or archival

Tip: JPEG does not support transparency. If you need a photo with a transparent background, use WebP or PNG.

PNG

Lossless compression — every pixel is preserved exactly. Supports full alpha transparency.

Best for: Screenshots, UI elements, logos on colored backgrounds, any image with text. Avoid for: Photographs (files will be 5-10x larger than JPEG).

PNG-8 vs PNG-24:

• PNG-8: 256 colors, smaller files, suitable for simple graphics
• PNG-24: 16 million colors, larger files, needed for photographs or gradients

WebP

Google's modern format that supports both lossy and lossless compression, transparency, and animation.

Best for: Everything on the web — it is the best general-purpose format. Avoid for: Print (limited software support), email (some clients don't display WebP).

Advantages over JPEG: 25-35% smaller at equivalent quality, supports transparency. Advantages over PNG: 26% smaller for lossless images, supports lossy compression. Browser support: 97%+ globally.

Convert and optimize images with our Image Optimizer.

SVG

Vector format based on XML. Images are defined by mathematical shapes, not pixels.

Best for: Logos, icons, illustrations, diagrams, any graphic that needs to scale. Avoid for: Photographs, complex raster images.

Unique advantages:

• Infinitely scalable without quality loss
• Tiny file sizes for simple graphics (often under 1 KB)
• Styleable with CSS (change colors, animate)
• Accessible (text in SVG is searchable and screen-readable)
• Editable in any text editor

<!-- SVG icon: 200 bytes vs PNG: 5,000 bytes -->
<svg width="24" height="24" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2">
  <circle cx="12" cy="12" r="10"/>
  <path d="M12 8v4l3 3"/>
</svg>

AVIF

The newest format, based on AV1 video codec. Superior compression to WebP.

Best for: Hero images, product photos, any high-priority image where maximum compression matters. Considerations: 92% browser support, slower encoding, limited editing tool support. Savings: 50% smaller than JPEG at equivalent quality.

GIF

The oldest web image format (1987). Limited to 256 colors.

Best for: Simple animations (but WebP animated is better). Avoid for: Almost everything else — WebP or APNG are superior alternatives. Legacy use: Still widely supported in messaging apps and social media for reactions/memes.

Size Comparison (Same Image)

A 1200×800 photograph optimized for web:

The same graphic (logo, 500×200):

Modern Best Practice: Picture Element

Serve the optimal format to each browser:

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

Browsers pick the first supported format. Everyone gets the best available quality at the smallest size.

Optimization Workflow

1. Start with the highest quality source — never optimize from a previously compressed image
2. Choose the right format using the decision chart above
3. Resize to display dimensions — don't serve a 4000px image in a 800px container
4. Compress — use our Image Compressor for quick optimization
5. Serve responsive sizes — use srcset for different viewport widths
6. Enable lazy loading — loading="lazy" for below-the-fold images

For more on optimization, see our Image Optimization guide.

FAQ

Should I convert all my images to WebP?

For web delivery, yes — WebP is the best general-purpose format with 97%+ browser support. Keep original files in their native format (JPEG, PNG) for archival and editing, and convert to WebP for serving. Use the <picture> element to provide JPEG fallback for the rare browsers that don't support WebP.

Is AVIF ready for production use?

AVIF is production-ready with 92%+ browser support. The main considerations are slower encoding (3-10x slower than WebP) and limited editing tool support. For static websites where images are encoded once during build, encoding speed is not an issue. Always provide WebP or JPEG fallback.

Related Resources

• Image Optimizer — Compress images for the web
• Image Resizer — Resize to exact dimensions
• Image Optimization for the Web — Complete optimization guide