How should I use this result?

Treat it as a fast decision aid. For execution-sensitive trades, check live bid, ask, fees, and slippage before acting.

Does this assume Polymarket-style binary settlement?

Unless a tool says otherwise, outputs assume binary shares settle to either $1 or $0 at resolution.

PerformanceFree utility

Score single predictions or batches of forecasts with Brier loss.

brier scoreforecast accuracycalibration

Adjust live

Calculator setup

Enter your assumptions and this tool will update immediately.

Rows (probability, outcome)

Instant

Primary output

0.1485

Mean Brier score

Live resultReady to copy

Observations

Keep the workflow moving with the next most relevant calculators.

Log Loss Calculator

Evaluate forecast quality with ignorance score / log loss.

Brier Skill Score Calculator

Measure your Brier improvement versus a baseline forecast.

Calibration Error (ECE) Calculator

Estimate expected calibration error from a forecast log.

Sharpness (Entropy) Calculator

Measure how concentrated or timid your forecasts are on average.