Images

How to Convert Images to WebP for Faster Websites

WebP delivers 25–34% smaller images than JPG at the same visual quality. This guide shows exactly how to convert, when to use WebP, and how to serve it with JPG fallback.

Difficulty
Intermediate
Time
15 min

Last updated

FixFile.online Team

The FixFile.online editorial team — file format specialists, developers, and technical writers focused on practical file-fixing solutions.

How to Convert Images to WebP for Faster Websites

WebP is an image format developed by Google that delivers:

  • 25–34% smaller than JPEG at equivalent visual quality
  • 26% smaller than PNG for lossless content
  • Full transparency support (unlike JPEG)
  • Animation support (unlike JPEG)
  • 97%+ global browser support as of 2024

Switching to WebP is the single highest-return image optimisation available for most websites.

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Step 1: Convert Your Images to WebP

  1. Open WebP Converter
  2. Upload your JPG, PNG, or GIF image
  3. Set quality to 85 — this is the recommended sweet spot
  4. Download your WebP file

Quality guide:

QualityFile SizeUse Case
90LargerPhotography portfolios, editorial
85MediumGeneral web use (recommended)
75SmallerThumbnails, background images
60SmallestLow-priority decorative images

Step 2: Verify the Output

Before replacing your original images:

  1. Open the WebP in Chrome (drag onto a tab)
  2. Compare visually with the original at 100% zoom
  3. Check file size — confirm the reduction is what you expected
  4. For images with transparency, verify the transparency is preserved

Step 3: Serve WebP With a JPG Fallback

WebP is not supported in very old browsers or some email clients. The standard HTML pattern uses <picture> to serve WebP with a fallback:

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

Browsers that support WebP use the <source>; others fall back to the <img> JPG automatically.


Step 4: Update Your CMS or Server

WordPress: Install the "Converter for Media" or "ShortPixel" plugin — they convert on upload and serve WebP automatically.

Next.js: The <Image> component from next/image converts to WebP automatically. No manual steps needed.

Nginx: Add a WebP rewrite rule to serve pre-converted WebP files to supporting browsers while serving JPG to others.

Shopify: Themes using Shopify CDN serve WebP automatically — no action needed.


Step 5: Measure the Impact

After deploying WebP images:

  1. Run a PageSpeed Insights test before and after
  2. Check the "Serve images in next-gen formats" audit — it should now pass or show significant improvement
  3. Compare total page weight in the Network tab of Chrome DevTools

Typical outcome: 20–40% reduction in total image payload, resulting in 1–3 second faster load times on mobile connections.


When Not to Use WebP

  • Email attachments — Outlook and Apple Mail do not display WebP inline; use JPG
  • Very old CMS or hosting — some platforms cannot serve the image/webp MIME type correctly
  • Image archival — keep original PNG/JPG masters for editing; WebP as delivery format only

Frequently asked questions

WebP produces images 25–35% smaller than JPG and 50–60% smaller than PNG at equivalent visual quality. Smaller images mean faster page loads, lower bandwidth costs, and better Core Web Vitals scores — all of which directly affect Google search ranking and user experience. Modern browsers (Chrome, Firefox, Safari 14+, Edge) all support WebP natively.

Only if you choose lossy compression and a low quality setting. At quality 80–85%, WebP is visually indistinguishable from the original JPG or PNG for most images. WebP also supports lossless compression (identical to the original at a smaller file size) and transparency (like PNG). Use lossy for photographs, lossless for screenshots and graphics with flat colours.

Use the HTML <picture> element with a JPG/PNG fallback: <picture><source srcset="image.webp" type="image/webp"><img src="image.jpg" alt="..."></picture>. Browsers that don't support WebP skip the <source> tag and load the JPG fallback. Internet Explorer is the main non-supporting browser; all other major browsers have supported WebP since 2021.