Write down what you think will happen. Note how confident you are. Over time, learn how well your hunches match the world.
50% is a coin flip. 99% means near certainty. The point isn't to be bold — it's to be honest about what you actually believe.
Resolved
0
predictions closed
Brier score
—
lower is better
Hit rate
—
of resolved
Streak
0
consecutive correct
Calibration curve
The dashed line is perfect calibration. Bars above it mean you're overconfident; bars below it mean you're underconfident. With few data points, expect bouncy results.
Brier score over time
A running average across your resolved predictions. Trending down means your forecasts are getting sharper.
Belief Tracker is a small tool for keeping track of your own predictions and seeing, over time, how often you're right at each level of confidence. It's based on a simple idea from forecasting research: good calibration is a learnable skill, and the only way to learn it is to write your guesses down before you know the answer.
Make a prediction with a clear resolution date. Pick a confidence between 50% and 99% — 50% is a coin flip, 99% is near certainty. When the date arrives, mark whether it came true. Visit the Calibration tab to see your patterns.
Predictions that don't have a clean yes/no answer aren't ideal for this tool. "I'll feel happier next month" is hard to score; "I'll finish the report by Friday" is easy.
Your Brier score is the average squared distance between your confidence and the outcome (0 or 1). A perfect forecaster gets 0; a coin-flipper hovers around 0.25. Anything under 0.20 across enough predictions is genuinely good.
Your calibration curve answers a different question: when you said you were 80% sure, were you right about 80% of the time? Bars above the diagonal mean overconfidence; bars below mean you were sandbagging.
Everything you write is stored in your browser's localStorage. Nothing is sent to a server. There is no account, no tracking, no analytics. Clearing your browser data will erase your predictions, so use the Export buttons periodically if you care to keep them.
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