About FoS

FoS: The Daily Load Test is a free daily puzzle for engineers and anyone curious about how things are built. Every day the lab tests five specimens, and everyone gets the same five.

The five tests

• Identify (3-point bend test): name the material, structure, machine, law or person from three clues.
• Dimension check (tensile test): name the physical quantity from its SI units.
• Sort it (torsion test): put four values in mixed units in order.
• Odd one out (column compression): three share something, so find the one that doesn’t.
• Calc (pressure vessel): solve a real engineering problem. The calculator and formula sheet are in Tools.

Scoring

Each round is worth a factor of safety of up to 3.0, so a perfect run is 15.0. Solve faster and your specimen holds at a higher load. Miss, and watch it fail. Mondays and Tuesdays are a light load, Fridays are heavy.

Who makes it

FoS is made by Matthew, a controls and automation engineer with a mechanical engineering background, with help from Claude, an AI model by Anthropic. Facts are checked against published sources. If you spot a mistake, please email feedback@fos-daily.win or use “Report a problem” in the game’s Settings. Corrections are always welcome.

Credits

Fonts: Archivo and JetBrains Mono, both under the SIL Open Font License, hosted on this site.