WebP vs JPG: Which Should You Use for Your Website?

WebP launched in 2010 and has been "the future of web images" ever since. Now it's simply the present every major browser released since 2020 supports it natively. But JPEG hasn't gone anywhere. Knowing when to use each saves significant page load time.

The Short Answer

Use WebP for new content. For backward compatibility, serve WebP with a JPEG fallback using <picture>.

That's the correct answer for 95% of situations. Here's the detail that explains why, and what the 5% looks like.

Format-by-Format Breakdown

JPEG (Joint Photographic Experts Group)

• Age: 1992
• Compression: Lossy only
• Transparency: No
• Animation: No
• Browser support: Universal (every browser, every device, ever)
• Typical web quality size: ~150 KB for a 1200px photo at quality 80

JPEG's main advantage in 2026 is compatibility. It works on every device ever made. Any tool that processes images handles JPEG. Any CMS accepts it. Any email client renders it.

Its main weakness is compression efficiency. You're paying more bytes for equivalent quality compared to WebP.

WebP

• Age: 2010 (widely supported since ~2020)
• Compression: Lossy or lossless
• Transparency: Yes (like PNG)
• Animation: Yes (like GIF but smaller)
• Browser support: All modern browsers (Chrome, Firefox, Safari 14+, Edge)
• Typical web quality size: ~100 KB for the same 1200px photo at equivalent quality

WebP is 25–35% smaller than JPEG at equivalent visual quality. That's not a marginal improvement across a full website, it meaningfully affects load times, Core Web Vitals scores, and bandwidth costs.

When WebP Wins

Almost always. Specifically:

• Blog post images browsers reading your blog all support WebP. The size saving is real.
• Product photos e-commerce pages load images constantly; smaller sizes mean faster loads and better SEO.
• Hero images the biggest image on the page. A 30% reduction here matters most.
• Images with transparency WebP supports alpha. JPEG doesn't. Previously this was PNG vs JPEG; now WebP replaces PNG for photos with transparency.
• Thumbnails in grids many small images loaded at once; the compound saving is significant.

When JPEG Still Wins

When compatibility is more important than size. Specifically:

• Email attachments most email clients still don't support WebP. Attach JPEGs.
• Sending to people without technical tools if a client will open the image in an older tool or Windows Photo Viewer, JPEG is safer.
• Uploading to platforms that re-encode Instagram, Facebook, and many other platforms re-encode images on upload anyway. The format you upload matters less; they'll convert it.
• Archival storage JPEG is a standard with a decades-long track record. WebP is too, but for "will this open in 30 years", JPEG is the safer bet.
• When you need broad tool support legacy CMS, old WordPress plugins, old Photoshop versions. These might reject WebP.

The Practical Comparison

Same photo, different formats:

WebP consistently wins by 25–40% at any quality level. The higher the quality setting, the bigger the absolute size saving (because the larger file has more bytes to save).

How to Serve Both

The <picture> element gives modern browsers WebP and older browsers JPEG automatically:

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

Browser reads top-to-bottom. If it supports WebP, it uses photo.webp. If not (Safari < 14, IE), it falls back to photo.jpg.

In React/Next.js, the <Image> component handles this automatically when you configure the formats:

// next.config.js
module.exports = {
  images: {
    formats: ['image/avif', 'image/webp'],
  },
}

Next.js serves AVIF to AVIF-capable browsers, WebP to WebP-capable browsers, and the original to everything else.

What About AVIF?

AVIF is the next generation after WebP typically 40–50% smaller than JPEG at equivalent quality. Browser support is now widespread (Chrome, Firefox, Safari 16+).

For new projects, consider the stack: AVIF → WebP → JPEG. Browser picks the first format it supports.

The catch: AVIF encoding is slower (minutes for a complex image on CPU-only encoders). For sites with many images, real-time AVIF encoding needs a CDN-level solution (Cloudflare Images, Imgix, Cloudinary).

Converting Between Formats

The WebP converter handles JPEG/PNG → WebP conversion entirely in your browser. Drop the file, choose quality, download.

For JPEG compression specifically (when you need to stay in JPEG format), the JPG compressor gives you a quality slider with live size comparison.

Neither tool uploads your images both run via the browser's Canvas API.

Quick Decision Table

Convert your images to WebP using the WebP converter. For JPEG compression when you need to stay in that format, use the JPG compressor. Both take under 30 seconds per image.