Off By
Rate itFive quick guesses a day about the numbers behind real life, and how far off you were.
on offby.io
Off By is a daily estimation game with five questions about real-world numbers, from app habits and prices to health and sport. You drag a slider or type your best guess, see how far off you were next to the crowd's average, and read the real figure with its source.
About Off By
Off By is a daily numbers game from Off By LLC, on the web since 2026 and as an app for iPhone and Android. Each day brings five quick questions about the real world: how many of 100 installed phone apps are deleted within a month, how much of a paycheck goes to taxes, how many out of 100 US prescriptions are generic. You will not know the exact number, and that is the point.
The home page shows the date and how far off the crowd has been today, then a Find out button starts the round. You answer by dragging a slider, tapping the arrows or typing a number, then lock in. The game shows how far off you were as a percentage, marks the crowd's average on the scale, and explains the real figure with a short fact and a named source. Each round is scored out of 500 points.
A round takes about two minutes and needs no account; signing in saves your streak across devices. Hints narrow the slider's range, and new players get one free. Friends can compare scores on their own leaderboard, each answer has a comment thread, and results can be shared as image cards.
It suits people who like Fermi-style guessing and want a small, surprising fact or two each morning.
How to play Off By
- Open Off By in the browser or the app and press Find out.
- Read the question and drag the slider, tap the arrows or type your guess.
- Use a hint if you have one to narrow the range, then press Lock In.
- See how far off you were, where the crowd's average landed and the real number with its source.
- Answer all five, then check your score out of 500, the leaderboard and come back tomorrow.
Screenshots
Tips
- Anchor on a number you know, such as the US population or a typical salary, and adjust from there.
- For out-of-100 questions, think about whether the answer is likely above or below half before fine-tuning.
- Read the fact after each answer: similar topics come back.
Questions
How many questions are there?
Five each day, the same for everyone, resetting at midnight.
Do I need an account?
No. The daily plays without signing in; an account saves your streak and progress across devices.
Does Off By have ads?
No. Its Google Play listing says no ads, and the web game shows none.
Is it only about the US?
Many questions use US figures, but topics range widely across money, health, technology, sport and pop culture.
Ratings and reviews
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