Image Converter

Batch-convert and resize images with a quality slider and aspect-ratio lock. Everything runs in a Web Worker via OffscreenCanvas — even 4K files won't freeze the page, and nothing is ever uploaded.

Drag & drop images here

or click to browse · PNG, JPG, WebP, AVIF, GIF, BMP · up to 50.0 MB

Files never leave your device — everything is processed locally.

Output format

Quality82%

Max width (px)

Max height (px)

Lock aspect ratio

Modern codecs

WebP and AVIF typically cut file sizes 25–50% versus JPEG at equal quality. Unsupported encoders are detected and disabled automatically.

Smart resizing

Set a max width, height, or bounding box. Aspect-ratio lock keeps proportions intact; unlock it to force exact dimensions.

Truly private

Decoding, drawing and encoding happen in a Web Worker on your device. Kill your Wi-Fi mid-conversion — it will still finish.