WebP is Google's next-generation image format that produces files 25–35% smaller than JPEG at the same visual quality — and up to 50% smaller than PNG for images with transparency. It's supported everywhere in 2026: Chrome, Firefox, Safari, Edge, iOS, Android, WhatsApp, WordPress, Shopify, and every major CDN. This converter takes any common image format — JPEG, PNG, HEIC from an iPhone, AVIF, animated GIF, BMP, TIFF, or SVG — and produces a WebP that's smaller, sharper, and faster to load. Everything runs in your browser using the same MozJPEG-quality WASM codecs Google uses in Squoosh. Your images never touch a server, so private photos, unreleased designs, and client work stay private.
Why convert images to WebP?
WebP consistently beats JPEG on size at the same visual quality — Google measured 25–35% smaller files across a large sample of photographic content, and independent audits (Cloudinary, Netflix, KeyCDN) have reproduced the result. For images with transparency, WebP replaces PNG at roughly half the file size while preserving the alpha channel losslessly. Smaller images mean faster page loads, less bandwidth billed by your CDN, and higher Core Web Vitals scores — especially LCP (Largest Contentful Paint), which is directly influenced by the size of your hero image. Google, Facebook, and every major CMS have supported WebP output for years, so there is no downside to shipping WebP as your primary format with JPEG/PNG as a <picture> fallback for very old browsers.
What formats can I convert to WebP?
This tool accepts every format the modern web deals with:
- JPEG / JPG — the classic photographic format. WebP typically saves 25–35% at equivalent quality.
- PNG — lossless raster with alpha. WebP lossy saves 50–80%; WebP lossless matches PNG size with slightly better compression.
- HEIC / HEIF — Apple's format for iPhone photos. Historically painful to open on Windows and Android; we decode it in-browser using libheif WASM so you never see a compatibility error.
- AVIF — the newest AV1-based format. If you need broader compatibility (some older browsers, image editors), convert AVIF → WebP.
- GIF — animated GIFs are converted to their first frame as a WebP still. For animated-WebP output, request a dedicated tool.
- BMP, TIFF — legacy uncompressed and scanned formats. WebP compresses them dramatically.
- SVG — rasterized at native size to WebP. Useful when you need a raster fallback for an SVG hero.
How is quality preserved?
The default preset — Balanced — uses WebP quality 80, method 4, and 4:2:0 chroma subsampling. In blind side-by-side tests these settings are indistinguishable from the source at normal viewing distance while producing files 60–75% smaller than the original JPEG. If you're archiving photos or serving hero art, switch to the Best preset (quality 92, 4:4:4 chroma) which is mathematically lossless for most images. For maximum page-speed impact, Smallest pushes quality to 62 with slower encoding — still passable for thumbnails and blog inline images, but you may see faint blocking on smooth gradients. The advanced panel exposes every parameter so you can dial in your own target: quality, effort (0–6), chroma subsampling (4:4:4 / 4:2:2 / 4:2:0), resize, metadata stripping, and a safety toggle that keeps the original if the encoder can't beat it.
Does anything ever leave my browser?
No. This tool loads MozJPEG, oxipng, libheif, and libwebp as WebAssembly modules directly into the browser. Every decode and encode happens in your own tab — files never appear in a network request, are never written to any server disk, and are never seen by any log. Open the browser Network tab while you drop a file: you'll see zero requests fire while the file is processed. That's why HEIC of family photos, unreleased product renders, medical images, and confidential client mocks are all safe to run through the tool. The only case where a file could leave your browser is if we fall back to a server-side converter for a codec your browser can't handle — this tool doesn't need to, so there is no fallback path here.
Batch conversion and downloads
Drop up to 20 images at once. Each file is decoded, converted, and re-encoded in sequence so WebAssembly memory stays bounded on low-end devices. Every file shows its own progress, thumbnail, before/after size, savings percentage, and per-file download button. When the batch finishes, hit Download all (.zip) to get a single ZIP archive with every optimized WebP — filenames preserve the original name and just swap the extension (photo.jpg → photo.webp). If you drop a file whose "optimized" output is somehow bigger than the source (rare, but it happens with very small already-optimized images), the tool keeps the original and tells you so.
Using WebP in HTML, CSS, and CMSes
Modern browsers (2020+) support WebP directly — you can drop it into <img src="hero.webp"> without any wrapper. For maximum compatibility including internal Windows tools or very old Android devices, use the <picture> pattern: <picture><source type="image/webp" srcset="hero.webp"><img src="hero.jpg" alt="…"></picture>. In CSS, both background-image: url('bg.webp') and gradients with a WebP fallback work everywhere in 2026. WordPress supports WebP uploads natively since 6.0; Shopify converts everything to WebP automatically; Next.js's <Image> component prefers WebP by default. There is no ecosystem left that punishes you for shipping WebP as your primary format.