Betting
📈 Expected Value (EV)
Find the true EV, edge and ROI of a single bet.
Result
—
How it works
The formula
EV = p×(stake×(dec−1)) − (1−p)×stake. Edge % = p×dec − 1.
Example: 100 @ 2.10, p=52% → EV ≈ +9.2, edge ≈ +9.2%.
FAQ
Questions
What is a +EV bet?
One whose expected value is positive: your estimated probability beats the odds’ implied probability.
Does +EV mean I will win?
No. It means profit over the long run if your probability estimate is accurate.
More tools
Related calculators
🔁
Odds Converter
Convert decimal, fractional, American, Hong Kong & implied probability instantly.
✂️
Vig Remover / True Odds
Strip the bookmaker margin to reveal fair odds and true probability.
🎯
Parlay / Accumulator
Combine up to 20 legs into one payout with combined odds.
🧩
System Bet (Lucky 15/31/63)
Trixie, Yankee, Lucky 15/31/63 — full breakdown of combination bets.
For entertainment & education only. OSOTOTO does not offer gambling. Results are mathematical estimates — variance means real outcomes differ. 18+. Need support? Self-check.
