Fermle

About Fermle

Fermle turns Fermi questions into a daily guessing game. Each day brings one numbered question, the same for every player, such as how many hours people watched on Netflix in a year, how many piano tuners work in Chicago, or how many ants live on Earth.

You do not need the exact figure. The goal is the right order of magnitude: if the answer is 85 million, any guess from 10 million to 99 million wins. You type a number (shorthand such as 500M or 2.5B works) and the game tells you to go higher or lower. You have five tries, and a hint is available if you are stuck.

Once you find the right power of ten, you get one bonus shot to get as close as possible, with colour showing how warm or cold you are and an arrow for the direction. The day's best players appear in a Today's Top 10, and the game offers Classic and Advanced modes.

It suits anyone who enjoys back-of-the-envelope reasoning and wants a quick daily number puzzle with a leaderboard.

How to play Fermle

1. Open Fermle and read today's question.
2. Type an estimate, using shorthand such as 1K, 1M or 1B if you like.
3. Follow the higher or lower hint to move to the next power of ten.
4. Find the right order of magnitude within five tries.
5. Use your bonus shot to get as close as you can, then check Today's Top 10.

Tips

• Break the question into a few rough factors and multiply them.
• Start in the middle of the plausible range so each hint halves what is left.
• Use the hint only after a guess or two, once you know roughly where you are.

Questions