Image Format Converter
Convert between PNG, JPG, WebP, and AVIF entirely in your browser. Set quality, preserve or strip metadata, and batch-process multiple files at once. No upload, no signup, no compression-quota limits — everything runs locally on your machine using the browser's native image decoders.
Why Format Conversion Still Matters
Different formats are good at different things. JPG is lossy, has no alpha channel, and produces the smallest files for photographs. PNG is lossless, supports transparency, and is the right pick for logos, screenshots, and anything with sharp edges. WebP is roughly 25-35% smaller than JPG at equivalent quality and supports both lossy and lossless modes plus transparency — it's the default modern web image format. AVIF compresses even better than WebP but lacks the universal support WebP enjoys, so it's usually shipped as a
The right format depends on where the image is going. Email attachments still want JPG for compatibility. Modern web pages want WebP with a JPG fallback. App icons want PNG for the alpha channel. Social media platforms each have their own preferences — Instagram converts everything to JPG anyway, so starting from JPG saves a round-trip of recompression.
How It Works
The tool uses the browser's Canvas 2D API. Each input image is decoded into a canvas, then re-encoded via canvas.toBlob() in the target format. The quality slider maps directly to the quality parameter of toBlob() for lossy formats (JPG, WebP, AVIF). For lossless conversions (PNG output, or WebP lossless), the quality slider is ignored. AVIF encoding uses the browser's built-in encoder where available — Chrome and Safari ship one, Firefox is still partial as of mid-2026. If the target format isn't supported by your browser, the tool surfaces a clear error instead of silently producing a corrupt file.
To compare what JPEG, PNG, WebP, and AVIF would each weigh at the same dimensions before converting, the File Size Estimator prints a side-by-side bits-per-pixel table.
Need to compress before converting? Run the input through the image compressor first. Need to resize? The bulk image resizer handles dimensions before format. For removing the background on a photo before converting, the background remover runs locally too.
Common Use Cases
Converting a folder of PNG screenshots to WebP for a documentation site (often 70% smaller, identical-looking). Producing JPG versions of design exports for email-friendly sharing. Stripping the alpha channel from a PNG by converting to JPG so a print service doesn't reject it. Generating AVIF versions to ship behind a
How We Compare
Cloud converters like CloudConvert and TinyPNG are excellent at compression — TinyPNG's algorithms are state of the art — but they upload your images. If the image is a product photo, a draft graphic, or anything internal, that's a non-starter. Desktop tools like ImageMagick and FFmpeg do everything this tool does and more, but require installation and command-line comfort. For a quick browser-based conversion of a few files, this tool is the lowest-friction path. For batch conversion of hundreds of files, a CLI tool will be faster.
Frequently Asked Questions
Built by Derek Giordano · Part of Ultimate Design Tools