See what your bet is actually worth.

Your book hides its cut in every line. Paste the market and actualodds rips the juice out: fair odds, true EV, and the exact stake to fire.

Free. Instant. No account needed.

comma starts a new leg · slash separates sides · your side goes first
the price you're offered: boost, promo, or parlay
when in doubt, leave it
ρ, or SGP odds
math ok: 100%*65%
 
Worst-case: methods to compare
Bankroll, Kelly & display
Enter leg odds and final odds to devig.

Where your edge leaks

Take a coin flip. A fair book would post +100 both ways. Yours posts −110/−110. Bet both sides and you lay out $220 to collect $210. That missing $10 is the vig: a tax sewn into every price on the board. Devigging backs the tax out. It looks at every side of a market, strips the margin, and hands you the probability the book is actually pricing. Stack that fair line against a boost or promo and the verdict is instant: positive EV, fire. Negative, walk.

New here? Set the bar high. Take +3% or better on mainlines (moneyline, spread, total) and +5% or better on props. True beginner? Hold out for +10%. And hear this: a +EV bet is not a promised win. It's the long game. The graph below shows the ride.

Your edge, played forward

An edge doesn't pay you on schedule. It pays you eventually, through swings that will test your nerve. Dial in your numbers and watch what a real bankroll does: the dashed line is the math, the wiggly ones are your life.

Stakes are ¼ Kelly of the live bankroll, same as the calculator. Past simulations don't guarantee future variance being kind.

Devig methods, explained

Books don't spread their cut evenly: longshots usually carry more of it than favorites. Four methods, four opinions on where the juice hides. Same market, watch +650/−900. The calculator's default takes the worst case across all four, so a play that survives doesn't depend on you picking right.

Multiplicative

Shaves every side by the same ratio. Goes easy on longshots. +650/-900 → +675

Best for: tight two-way markets near even money: spreads and totals at standard juice.

Additive

Takes an equal bite of raw probability from each side, which lands harder on the longshot. +650/-900 → +757

Best for: two-way markets with a modest favorite: moneylines around −150 to −250.

Power

Fits an exponent to the whole market. Harshest on longshots, kindest to chalk. +650/-900 → +815

Best for: lopsided markets: heavy favorites, big dogs, alt lines and boosted longshots.

Shin

Models a book defending itself against sharp insider money. Matches additive on two-way markets, splits from it on three or more. +650/-900 → +757

Best for: multi-way markets: futures, outrights, first-scorer props.

Speak its language

Type odds the way you already think about them. Five short lessons, ten seconds each. Tap any example to load it live.

Legs & markets start here

A comma starts a new leg. A slash separates the sides of one market. Your side goes first. That's 90% of it.

Your side, then theirs+240/-310try
Parlay: stack legs with commas-115/-105, +130/-155try
Multi-way market: list every runner+360/+220/+700/+1100try
Backing two runners? Glue them with ^+475^+625/+900/-170try
Either bet can cash (independent)-130/+105||-160/+130try
Leave yourself a note+240/-310 // out by Sunday
Only one side posted?

No other side on the board? Tell it the juice and it rebuilds the market for you.

Assume the juice yourself+310/6%try
Borrow the juice from a market you can see+310/[-122/-102]try
Blend books & lines

One book's price is an opinion. Several books are a consensus. Mix them inline.

Average a few booksAVG(-142,-138)/AVG(+118,+122)try
Shortest or longest price winsMIN(-145,-150)/+125try
You already know the hit rateHIT(58%)/4%try
Your line sits between two posted onesINT(25.5;23.5=-175,27.5=-115)/4.5%try
Boosts, promos & strange payouts

The Final Odds box prices whatever the promo desk dreams up. Whole payout tables included.

A boosted price+350try
Final odds quoted as a parlay-135,-250 → it prices to +144try
Parlay insurance: 3 hit pays the parlay, 2 hit refunds half3=-260,-220,-190;2=0.5xtry
Risk-free bet (r = what the refund is worth to you)1=+250;r=0.65xtry
Win & get a bonus on top1=-240;w=0.6xtry
Get it win or lose1=-550;n=0.3xtry
Boost box does math100%*65% (full boost, paid in 65¢ bonus dollars)
Correlated legs

Same-game legs move together, and pretending they don't will torch your EV math. Tell it how much.

You know the correlation0.25try
Let the book confess: their SGP price vs their own legs+155=-190,-120try
Full SGP market: all four combos, then each leg135/550/850/125=-125/-105,110/-135

The juice

Short reads on betting math. No picks, no fairy dust.