oldphotocolor // neural photo colouriser, on your device

Colourise without uploading your photos

notes · 03 · 5 jul 2026

family photo upload + subscribe? a paid server the model runs here
fig — the archive never has to leave home.

Colourising old photos is one of the most personal things people do with software — and, until recently, one that quietly demanded you upload your family history to someone else's servers, often behind a subscription. The photos of grandparents, weddings and childhoods are exactly the images you'd least want sitting in a stranger's cloud.

The old trade-off is gone

Colourisation needs a real neural network, and for years that meant a server, because browsers couldn't run one. That's no longer true. WebAssembly lets a full colourisation model execute inside the tab, on your own processor. This tool downloads the model once (it's sizeable, because it's the real thing), then runs entirely locally — you can add colour to a hundred photos, on a plane, with the network off, and not one of them is transmitted anywhere. No account, no subscription, no upload.

Why it's worth the one-time download

The catch is honest: a genuine model is tens of megabytes, so the first colourisation waits for that download. After that it's cached and instant. That trade — a one-time download in exchange for your photos never leaving your device — is the whole point. A cheaper site would upload your image to skip the download; that's precisely what you don't want for a shoebox of irreplaceable family pictures. Run the model where the photos already live, keep the originals private, and share only the colour versions you choose to.