Universal Bet Calculator & Optimizer

The all-in-one betting analysis tool. Enter odds from multiple sportsbooks and instantly find arbitrage opportunities, +EV bets, market holds, best odds, cross-book synthetic parlays, and parlay dutching across books — all in one place.

Arb Finder+EV DetectionHold CalculatorBest OddsOdds ConverterPayout CalculatorKelly Sizing5 Devig MethodsSynthetic ParlaysScenario MatrixParlay Dutch

Covers 20+ sportsbooks · 3 market types · 5 devig methods · Free, no signup required

How It Works

1

Enter Odds

Add 2+ sportsbooks with moneyline, spread, or total odds for any game. Supports American, decimal, and fractional formats.

2

Analyze

The engine compares every combination across all books and markets — calculating holds, fair odds, EV, and optimal stakes.

3

Find Opportunities

See arbitrage bets, +EV plays, best available odds, middles, cross-book parlays, parlay dutching across books, and full scenario matrices.

Parlay Dutch: Cover Every Outcome Across Books

Parlay dutching is a cross-book strategy that covers every possible outcome combination across multiple games. Instead of betting individual sides, you place a complete multi-leg parlay at one sportsbook for each combination — and size your bets so every scenario pays the same guaranteed amount.

How It Works — Step by Step

  1. Pick your games — Enter odds from multiple sportsbooks for 2+ games (moneyline, spread, or total).
  2. Engine calculates every outcome combination — With 3 games and 2 outcomes each, that's 2 × 2 × 2 = 8 possible results.
  3. Find the best single-book parlay for each combo — For each of the 8 combinations, the engine checks every sportsbook's parlay price and picks the best one.
  4. Dutch-size your stakes — Bets are sized proportionally so that no matter which combination hits, the payout is identical.
  5. Check total implied probability — If the sum of all implied probabilities (1 / decimal odds for each best-priced parlay) is under 100%, you profit regardless of outcome.

Why It Works

Different sportsbooks price parlays differently. A 3-leg parlay at DraftKings might pay +650, while the same combination at FanDuel pays +720 and at BetMGM pays +680. By shopping the best single-book price for each outcome combination, you exploit cross-book pricing inefficiencies that don't exist at any individual sportsbook.

Why Parlays Instead of Single-Game Arbs?

Each bet looks like a normal recreational parlay placed at a single sportsbook — because it is one. Sportsbooks are far less likely to flag or limit parlay bettors compared to someone hammering both sides of a single market. The strategy hides in plain sight.

Whether you profit depends on the total implied probability being under 100% — not every set of odds produces a parlay arb. The tool calculates this automatically and clearly shows whether the current odds represent an opportunity.

Enter odds from any 2 sportsbooks to instantly find arbs, +EV bets, and best odds.

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Side 2
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Frequently Asked Questions