The pros don't bet with their gut. They bet with math. Learn the unit system, find +EV edges, and never risk money you can't afford to lose.
Every professional sports bettor follows these principles. They're not optional — they're how you survive long enough to win.
Your bankroll — your "purse" — is money set aside specifically for betting. Not your rent. Not your savings. Not your credit card. It's money you can afford to lose entirely without changing your life. Fund it once, protect it always.
A standard wager is one unit — exactly 1% of your purse. If your purse is $1,000, one unit is $10. This isn't conservative, it's mathematical. At 1% per bet, you'd need to lose 100 straight bets to go broke. That doesn't happen if you're betting +EV.
Expected value (+EV) is everything. If a bet's true probability of winning is higher than the odds imply, the bet is +EV — and over time, you profit. If it's not +EV, you don't bet. Not because the game is exciting. Not because you have a hunch. Only math.
Enter the odds, estimate the true probability, and know instantly whether a bet is worth placing.
Type into any field and the others update instantly. All three formats represent the same probability.
Every term you'll encounter, explained without the jargon. Search or browse.
Bookmark the calculator. Set your purse. Only bet +EV. That's the entire system — and it's the only one that works long-term.
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