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Calculate before interpreting

Probability and gambling-cost tools

These educational calculators make implied probability, built-in odds margin, total turnover and losses visible. They run only in your browser and predict no outcome.

Probability notebook and calculator on a study desk
A calculation describes a structure or record; it never turns a negative-expectation game into income.
01

Implied probability from odds

Decimal odds of 2.00 correspond to 50% before margin.

Implied probability—
02

Margin in an odds market

Enter every decimal price from one market, separated by spaces or semicolons.

Probability sum and margin—
03

Total turnover and theoretical loss

Repetition increases exposure: stake × rounds, then turnover × edge.

Turnover and theoretical loss—
04

Observed net loss

Add all deposits, then subtract completed withdrawals and the balance still available.

Net loss—

Result

What these results do not say

Probability is not a prediction

A 25% chance may or may not occur next. It describes theoretical frequency, not a promise.

Theoretical loss is not a ceiling

A short session can lose far more than the calculated average. Variance often dominates the short term.

Turnover can exceed deposits

Replaying a win increases total exposure without another payment. Tracking real cash flows remains essential.

Margin does not include every cost

Commission, exchange fees, bonus conditions, tax or pricing errors may change the real cost.

Formulas used

  1. Implied probability = 100 ÷ decimal odds.
  2. Gross margin = sum of implied probabilities − 100.
  3. Turnover = stake per round × number of rounds.
  4. Theoretical loss = turnover × theoretical edge.
  5. Net loss = deposits − withdrawals − available balance.