Streak Betting Tool
Calculate the probability of winning or losing streaks from your win rate and run length.
How to Use This Calculator
- Enter your single-bet win probability as a percentage (for instance, 55)
- Enter the streak length you wish to evaluate
- Enter the total number of bets
- Review the streak probability together with the expected longest run
Formula
P(streak of N wins) = p ^ N
P(streak of N losses) = (1 − p) ^ N
Expected Longest Run (approx) = log(N · (1 − p)) / log(1 / p)
P(≥ 1 winning streak of length N in M bets) ≈ 1 − (1 − p^N)^(M − N + 1)
Frequently Asked Questions
Why does my expected longest streak appear so lengthy?
Variance grows logarithmically as the sample expands. Across 1000 coin flips you will routinely encounter a run of 9-10 heads. Long streaks feel startling yet are mathematically anticipated, and most bettors misread them as hot or cold spells rather than ordinary variance.
How does streak length influence bankroll management?
Even a 60% win rate throws up losing streaks of five or more on a regular basis. Your bankroll management, whether Kelly fractions or flat staking, has to absorb these without collapse. Run this calculator with a streak length of 5-7 to gauge how often such losing runs surface, then size your unit accordingly.
Do sports streaks have any predictive power?
For the most part, no. Independent events, those resembling coin flips, generate streaks purely by chance. Modest predictive effects can exist, such as injury cascades or team morale, but they are usually exaggerated. Treat past streaks as variance unless you hold concrete, model-based grounds to think otherwise.
What is the mathematics behind the 'expected longest run'?
For independent Bernoulli trials with success probability p across N trials, the expected longest run of successes converges toward log(N(1−p))/log(1/p). It is a logarithmic approximation, accurate for large N, that yields the typical longest streak you would expect to observe.