Convert JPG or PNG to WebP: When It Helps and How to Do It

The short answer

Converting to WebP is worth it for images on your own website, where smaller files load faster, and it keeps PNG transparency. Upload a JPG or PNG to the free Image to WebP converter and compare the before and after sizes it shows; keep the WebP only if it is smaller. Use Chrome, Edge or Firefox for this, because Safari cannot create WebP files from a web page.

What WebP is

WebP is an image format developed by Google that supports both lossy compression (like JPG) and lossless compression (like PNG), plus transparency and animation. All major current browsers can display it, including Safari since version 14 (2020), so WebP images on a website will show for almost all visitors.

When converting to WebP helps

• Website and blog images. Smaller images make pages load faster, especially on mobile data.
• PNG screenshots and graphics with transparency. WebP can keep the transparent background, while converting to JPG would fill it with white (see why PNG to JPG turns the background white).
• Large photos straight from a camera or phone, when you also resize them to the size actually displayed.

When it does not help

• Upload forms and government portals. Many accept only JPG, JPEG or PNG. A WebP file may be rejected. For those, use the Compress Image to KB tool instead.
• Emailing or printing photos. Some older apps and printers still do not open WebP. JPG is the safer choice for sharing.
• Small images that are already heavily compressed. Re-encoding an already compressed JPG can produce a WebP that is the same size or even larger. The tool shows both sizes, so you can see this immediately.
• Editing master copies. Every lossy save loses a little detail. Keep your original files and create WebP copies only for publishing.

How to convert an image to WebP

Open Image to WebP in Chrome, Edge or Firefox.

Drop a JPG, PNG or other image onto the upload area (up to 30 MB).

The image is converted in your browser; it is not uploaded to a server.

Compare the original size and new size shown on screen.

Click Download WEBP. The file keeps its name with a .webp extension, for example banner.png becomes banner.webp.

What the converter does to your image

• Same pixel dimensions. It does not resize. A 4000 × 3000 photo stays 4000 × 3000.
• Fixed quality setting. It uses a high lossy quality setting (0.92 on a 0 to 1 scale). There is no quality slider, so the result is meant to look the same as the original rather than to be as small as possible.
• Transparency kept. Transparent areas in a PNG stay transparent.
• One frame only. An animated GIF becomes a still image of a single frame.
• Metadata removed. Because the image is redrawn, camera details such as EXIF data and location are not carried into the new file.

Why Safari users should use another browser

The converter relies on the browser's built-in image encoder. Chrome, Edge and Firefox can encode WebP; Safari on Mac, iPhone and iPad currently cannot. In Safari the browser falls back to producing a PNG, so the downloaded .webp file would really be PNG data, often larger than the original. If you use an iPhone or Mac, open the tool in Chrome, Edge or Firefox, or convert on a different device.

You can spot this problem if the "new size" is much bigger than the original, even for a photo.

Getting the smallest files

Format is only one part of image size. In practice, these steps usually save more:

Resize first. If an image is displayed 1200 pixels wide, there is no need to upload a 4000-pixel original. Use Resize Image to set the width, then convert.

Convert to WebP and compare the sizes.

If you need an exact target size in KB, use Compress Image or Compress Image to KB, which let you trade quality for size.

Checking that the file really is WebP

After downloading, a few quick checks confirm the result:

• Compare the sizes on screen. For a typical photo or screenshot, a real WebP at this quality is usually not dramatically larger than the original. A file several times bigger is a warning sign, especially in Safari.
• Open it in Chrome, Edge or Firefox. Drag the file into a browser tab to view it.
• Check the file details. On Windows, right-click and choose Properties; on a Mac, use Get Info. The type should show WebP. If an app reports PNG data for a .webp file, convert again in a supported browser.

If you need a JPG again later, convert from your original file rather than from the WebP, so you do not stack two rounds of compression.

Using WebP on a website

• Most modern content management systems accept WebP uploads. Check your platform's media settings if an upload is refused.
• Write meaningful alt text for each image; the file format does not change this.
• If you need to support very old browsers, the HTML picture element lets you offer a WebP file with a JPG fallback.

Quick decision guide

Situation	Best format
Photo on your own website	WebP (keep if smaller)
Logo or graphic with transparency on a website	WebP or PNG
Form or exam portal upload	JPG or as the portal specifies
Sending a photo by email or chat	JPG
Archiving originals	Keep the original file

The guide to whether converting JPG to PNG improves quality explains the same principle from the other direction: changing the format never restores detail that compression has already removed.