Convert PNG and JPG to WebP for Faster Websites

Images are usually the heaviest part of a web page, and a heavy page loads slowly, especially on a phone. WebP is a format designed to make the same picture smaller, which makes it one of the easiest speed improvements you can make. It is not magic, so here is what to expect and how to do it safely.

How much smaller is WebP

WebP stores pictures in smaller files than JPG or PNG at a similar look.

• Compared with JPG, WebP is typically about 25 to 35 percent smaller for photographs at a similar quality.
• Compared with PNG, WebP can be much smaller for photographs and screenshots, often 70 to 90 percent smaller, and it still supports transparency. For very simple flat-colour graphics, the saving is smaller because PNG already compresses those well.

The saving depends on the picture, so convert a sample and compare. The converters show the size of every result.

Converting your images

Use JPG to WebP for photographs and PNG to WebP for graphics, screenshots and anything with transparency.

1. Add up to 30 images.
2. Set the WebP quality. For photographs, 80 to 85 percent is a good balance. For text-heavy screenshots, use 90 to 95 so letters stay crisp.
3. Convert, compare the sizes, and download the files or a ZIP.

Both conversions happen in your browser, so your images are not uploaded.

Resize before you convert

The biggest saving usually comes from the dimensions, not the format. A photo displayed 800 pixels wide does not need 4,000 pixels. Run the pictures through the Image Resizer first, then convert them. How to compress images for faster websites walks through the whole process.

Browser support and fallbacks

All current major browsers can display WebP, so a modern website can use it directly. Outside the browser, support is patchy: older photo editors, some print shops, email clients and upload forms may not open it. Keep the original JPG or PNG alongside the WebP, so you can use it where WebP is not accepted. If you need to go back, WebP to JPG and WebP to PNG convert in the other direction.

For websites that must support very old browsers, serve a JPG or PNG fallback with the HTML picture element, which lets the browser choose the first format it understands.

Measure the real saving

Do not trust a percentage you read somewhere; measure your own pages. Open your browser's developer tools, go to the network panel, reload the page and compare the transferred size of the images before and after. Test with a throttled connection to see what a phone on a slow network experiences. A change that saves 300 KB on a page with twenty images is worth having; one that saves 2 KB on a single icon is not worth the effort.

What conversion cannot do

• It adds a small further loss. Both formats are lossy for photographs, so converting a JPG to WebP is a second compression. Convert from the original when you can.
• It cannot recover detail. A low-quality JPG stays low quality.
• It does not make an oversized image the right size. Dimensions are separate from format.
• Animations. Animated images convert to a single still frame in these tools.

A short plan for a site

1. Keep your masters in a folder you never overwrite.
2. Resize to the largest size the layout uses.
3. Convert to WebP at 80 to 85 percent for photos.
4. Use the Image Compressor if you want a size cap.
5. Test the page on a slow connection and check for visual differences.