Book A return
$230.00
Bad-line tax
Same bet, different book, different payout.
Two sportsbooks can post very different numbers on the exact same outcome — +820 at one, +700 at another. Enter a stake and two American odds prices below and see the gap. This is the "bad-line tax": what a worse number quietly costs you if the bet wins.
Book B return
$200.00
Book A shows more
$30.00
This shows the potential payout difference if the bet wins.
American odds only — enter values like +820, +700, or -110. Total return includes your stake back.
Why it matters
A few points of price adds up.
A single line looks harmless — thirty dollars here, ten there. But you don't place one bet. Over a season, taking the weaker number again and again is a steady leak: the same wagers you were going to make anyway, just paying out less. The fix isn't a hotter take. It's checking the price first.
- The bigger the underdog price, the bigger the gap between books.
- The math is just arithmetic on the displayed price — no forecast of who wins.
- BetVantage lines up your books and highlights the strongest number automatically.
Read this first
This does not predict an outcome. It shows how two prices change your total return if the bet wins — nothing more.
Odds, availability, and limits move. Always confirm the current price directly with the sportsbook before you bet.
BetVantage is not a sportsbook. We don't take wagers or hold your money — you bet directly with your own book. 21+.
Check the price before you bet, every time.
BetVantage compares the real number across the books you use. BetVantage is free — every feature, every sport.