Bild Werkstatt

The idea

Most image tools on the web want an upload before anything happens — the image travels to a server you don’t control, often with no clarity about what happens to it next. Bild Werkstatt turns that around: drag an image into the tab, process it there, and it never goes anywhere. There is no server to receive it — reload the page and every image is gone from memory.

Resize by pixels, percent or longest edge with an aspect-ratio lock, crop to common ratios, rotate and flip, convert between JPEG, PNG, WebP and AVIF, and compress with a quality slider — all per image or as a batch with one shared settings panel. The result is a single file or a ZIP with everything.

AI upscaling without a server

Instead of just stretching pixels when enlarging, a Real-ESRGAN model reconstructs missing detail — compact enough to run in the browser. Where available, WebGPU handles the computation, otherwise a WebAssembly build takes over. The model works on tiled sections so even larger images get through without memory issues, and transparent areas are treated separately so edges don’t get a dark fringe. For very large source images, a classic Lanczos resize takes over instead.

Format conversion and compression run through jSquash — WebAssembly ports of MozJPEG, libwebp, libavif and OxiPNG, loaded only on first use. The actual work happens in up to two Web Workers, so the interface stays responsive while processing runs.

More than a converter

• Batch processing: one settings panel for all images, download individually or together as a ZIP.
• Metadata (EXIF, GPS) is always removed — EXIF orientation is applied first, so rotated photos stay the right way up.
• Before/after compare view and a keyboard-accessible crop box for accessibility.
• Supported input formats: JPEG, PNG, WebP, AVIF, GIF (first frame), BMP, SVG.
• Limits of 100 MB per file, 50 megapixels and 200 images keep a large batch from overwhelming the tab.

Privacy without a server

With no backend, there is nowhere for an image to flow to — processing happens entirely in the tab, in Web Workers and, for AI upscaling, on your own GPU or CPU. There is no localStorage for image data, only a single stored setting for the chosen theme. A dedicated test script checks after every build that the shipped site contains no addresses to other servers.

Like this portfolio, Bild Werkstatt is built statically, ships in German and English, and gets by without cookies or tracking.