Download websites that use Darkmode.js

About Darkmode.js

A dark mode toggle is a small feature with a revealing procurement story. A team that builds theming into its own design system never loads a script to do it. Darkmode.js appears when somebody wanted the feature quickly, in a single tag, on a site that already existed and was not going to be rebuilt for it.

The library is MIT licensed, written in JavaScript, and dates to 2019, which places it in the wave of front end utilities that spread through template marketplaces, theme bundles, and tutorial posts rather than through package managers and build pipelines. As of October 2026 we see it on 94 sites.

Version behaviour is where the population becomes interesting. We observe 9 distinct versions in the wild, and the release our current export reports as the common one is 1.5.7. A script installed by pasting a tag is pinned to whatever was current on the day it was pasted, and nothing ever moves it forward, so the version spread is really a record of when each site was last touched by a human. Where a build pipeline carries a dependency along silently, a pasted tag freezes it, and frozen versions accumulate in layers.

For anyone studying front end maintenance that property is the value of the list. A domain serving an old pinned copy of a small utility is usually a domain nobody has rebuilt in years, and the same domains tend to carry other frozen dependencies beside it. Security researchers use the correlation to find unpatched populations, agencies use it to find redesign work, and platform vendors use it to estimate how much of their theme ecosystem is running code that predates the current browser generation.

Detection has a boundary worth naming. We can match the library when it is served from the page or from a public content delivery network, but a copy that has been renamed, minified into a site's own bundle, or inlined into the markup loses the signature we rely on, so the real footprint of the technique is wider than the count of recognisable installs.

Within that boundary the export answers what checking one domain cannot. Which versions persist and where, which sites still serve the oldest releases, whether the population is contracting as native colour scheme support in browsers makes an overlay unnecessary, and which themes or site builders ship the library by default and therefore drag it along behind them.