Expected value (EV)
Enter the price you can take and your honest estimate of the true chance. The calculator returns EV% and EV$ — the same edge number EVSTREAM shows on every runner.
A reality check on a strategy: at a given strike rate and average winning price, are you actually ahead? Return per $1 = strike rate × average odds.
See EV% on every runner
No guessing the true chance; EVSTREAM de-vigs it for you, live across 60+ books
Edge is just price × chance.
- ▸Positive EV means a long-run edge. +10% EV doesn’t win every time — it means that, repeated, you’d expect to make 10c per dollar staked.
- ▸Your true chance is everything. The hard part isn’t the maths — it’s estimating the real probability. De-vigged fair odds are the best honest estimate, which is why EVSTREAM feeds it straight in.
- ▸A high strike rate can still lose. Use the second tab: win 25% at $4.50 and you’re ahead; win 25% at $3.50 and you’re bleeding. Price matters more than how often you win.
Expected value, answered.
The number every value bettor lives by.
What is a +EV bet?
A bet whose expected value is positive — the price on offer is longer than the true chance justifies. Over many such bets you'd expect to profit, even though any single bet can lose.
How do I know my "true chance"?
You estimate it. The sharpest estimate is the de-vigged fair odds from a strong market — strip the margin and the implied probability is your best read of the real chance. That is exactly what EVSTREAM computes for you.
Does +EV guarantee I'll win?
No. EV is a long-run average. Variance means losing runs happen even with a real edge — which is why staking discipline (see the Kelly tool) and a large sample matter as much as finding the edge.
What's the strike-rate tab for?
To sanity-check a strategy from the other direction. Plug in how often you win and your average winning price, and it tells you the return on turnover and the break-even strike rate you'd need. It often reveals that winning “most” bets isn't the same as winning money.
Related guide
The Relationship Between Probability, Expected Value, and Strike Rate
Know the edge before you stake.
EVSTREAM computes EV against de-vigged fair odds for every runner, every bookie — live. Stop doing it by hand.