What this image converter does
Drop in iPhone HEIC photos, WebP or AVIF images saved from websites, PNG screenshots, scanned TIFFs, old BMPs, favicons or SVG logos. Each file gets its own target format, so one batch can turn HEIC photos into JPG while a logo becomes an ICO.
Open the options (the slider icon) on any file to set a width or height, pick the JPG, WebP or AVIF quality, choose the background colour used when transparency has to be removed, or select which sizes go into an ICO file.
Which format should I choose?
For sharing photos with anyone, JPG is the safe choice. For graphics, screenshots and anything with transparency, use PNG. For your own website, WebP is smaller than both and is supported by every current browser; AVIF is smaller again but slower to encode. ICO is only for favicons and Windows icons, and TIFF for print shops and archives that ask for it.
How the conversion works
Standard formats are decoded by your browser’s own image engine. HEIC uses libheif and AVIF encoding uses libavif, both compiled to WebAssembly and downloaded only when you add a file that needs them. TIFF is handled by UTIF.js and GIF palettes by gifenc. The pixels never leave your device; see how it works for details.