Skip to main content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Kids

The Measurement League: Guardians of the S.I. use their incredible powers of measurement to perform amazing feats of science and engineering.

Emerging from their environmentally shielded world headquarters at NIST, the superheroes are dedicated to the fight against uncertainty, imprecision and inaccuracy and to improving the quality of our lives and the things we build.

The Measurement League's work is never done. They toil tirelessly behind the scenes to make sure the measurements that interweave our lives are as accurate and precise as possible. And they hope to release another of their harrowing adventures to the public soon.

In their pilot episode, Desperate Measures, the Measurement League uses the power of measurement to help a stranded soccer player get home:

In their second suspenseful episode, Running Out of Time, the League battles archvillain Major Uncertainty in a race to keep the world's satellite navigation system "on time" to help a traveler and his son lost in the desert:

In their third episode, the nefarious Major Uncertainty has kidnapped Monsieur Kilogram, putting the world's measurements of mass in jeopardy. As the world spirals into Mass Hysteria, the remaining S.I. Superheroes, champions of the metric system, leap into action to save the day, and hopefully Monsieur Kilogram as well: