Are my images uploaded to a server?

No. The conversion runs entirely in your browser using the HTML canvas API. Your images never leave your device.

How accurate is the conversion?

WebP is re-encoded from the decoded JPG, so it reproduces the source faithfully. At the same visual quality WebP files are typically 25–35% smaller than JPG; very low quality settings can introduce visible artefacts.

Why does my browser say it can't encode WebP?

A few older browsers cannot write WebP from the canvas. If you see that message, use an up-to-date Chrome, Edge, Firefox or Safari — the tool detects this and tells you instead of producing a wrong file.

Is WebP supported everywhere now?

Yes for display — all current browsers (Chrome, Edge, Firefox, Safari 14+) show WebP. The main gaps are some older software and a few email clients, so keep a JPG copy if you need maximum compatibility.

What quality should I choose?

The slider runs 10%–100% (default 85%). Around 80–85% gives the best size-to-quality trade-off for web photos. Go higher only when detail is critical; very low values can blur fine texture.

Will converting to WebP improve my page speed?

Usually yes — smaller image bytes mean faster loads and better Core Web Vitals (LCP). The tool reports the exact percentage saved per file so you can see the gain.

Can I convert several JPGs at once?

Yes. Drop multiple files and they are all converted at the same quality, each showing its size saving and a download button.

What is the JPG to WebP Converter?

Free JPG to WebP converter. Turn JPEG photos into smaller WebP images instantly in your browser, with an adjustable quality slider — no upload, no signup, your files never leave your device. It runs free in your browser on Gera Tools, with nothing uploaded.

JPG to WebP Converter

Name: JPG to WebP Converter
Creator: Gera Tools
License: https://creativecommons.org/licenses/by/4.0/

Convert JPG to WebP in your browser

This tool converts JPG/JPEG photos to WebP entirely in your browser, with a quality slider and a live before/after size readout. WebP delivers the same visual quality as JPG at a noticeably smaller file size, which makes web pages load faster and improves Core Web Vitals — useful for developers, bloggers and anyone optimising images for the web.

How it works

Each JPG is decoded, drawn onto an HTML <canvas> at native resolution, and re-encoded with canvas.toBlob("image/webp", quality). The tool checks the returned blob is actually image/webp — if the browser can’t encode WebP it shows a clear message rather than handing you a wrong file. For every image it reports the original size, the WebP size and the percentage saved.

Example

A 1.4 MB hero.jpg at the default 85% quality typically becomes a ~0.9 MB hero.webp — about a −35% saving — with no visible difference at page size. Across a gallery of a dozen images that can shave megabytes off a page load.

WebP quality	Look	Typical saving vs JPG
90%	Visually identical	~20–25%
85% (default)	Imperceptible loss	~25–35%
70%	Slight softening	~40%+

Why WebP is smaller than JPG

JPG uses Discrete Cosine Transform (DCT) compression developed in 1992. WebP uses a newer codec derived from the VP8 video format developed by Google in 2010. The key technical differences:

Better entropy coding — WebP uses arithmetic coding instead of JPG’s Huffman coding, extracting more compression from the same data.
Larger transform blocks — WebP can process larger regions of an image in one pass, reducing redundant block boundary artefacts.
Predictive coding — WebP predicts pixel values from neighbouring blocks before encoding, reducing the information that needs to be stored.

These improvements combine to deliver smaller files at the same visual quality. The saving is most pronounced on photos with smooth gradients and large areas of similar colour; images with high-frequency detail (sharp edges, fine texture) see smaller but still meaningful gains.

Impact on page speed and Core Web Vitals

Images are typically the largest assets on a web page and a primary driver of Largest Contentful Paint (LCP), one of Google’s Core Web Vitals. Converting images from JPG to WebP is one of the highest-leverage single actions for improving LCP scores because it reduces byte transfer without changing layout or rendering behaviour. Lighthouse and PageSpeed Insights both flag JPGs that could be WebP as an opportunity — converting them removes that flag.

Browser support

All current browsers support displaying WebP: Chrome, Edge, Firefox, Safari 14+. The main gaps are older Safari versions (before version 14, released in 2020), some older Android browsers, and a handful of email clients. For broad compatibility, serve WebP using an HTML picture element with a JPG fallback, or use a CDN that negotiates the format via the Accept header.

Everything happens locally — your images are never uploaded, stored, or seen by anyone.