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.
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.