house-edge-calculator

Calculate house edge, RTP (return to player) and expected loss for common casino games: dice, crash/limbo, roulette and blackjack. Zero dependencies, ~2 KB.

🖥 Essayez-le dans le navigateur : Calculateur d'Avantage de la Maison (outil gratuit, sans inscription)

Install

npm install house-edge-calculator

Usage

import {
  diceEdge,
  crashEdge,
  rouletteEdge,
  blackjackEdge,
  rtp,
  expectedLoss,
} from 'house-edge-calculator';

// Dice: win chance (%) and the payout multiplier offered
diceEdge(50, 1.98); // 1.0 (%)

// Crash / Limbo: house edge equals the commission per round
crashEdge(1); // 1 (%)

// Roulette: number of zero pockets and total pockets
rouletteEdge(1, 37); // 2.7027... (European)
rouletteEdge(2, 38); // 5.2631... (American)

// Blackjack: approximate edge from the rule set
blackjackEdge({ decks: 8, h17: false, blackjackPays: '3:2' }); // 0.46
blackjackEdge({ decks: 8, h17: false, blackjackPays: '6:5' }); // 1.85

// RTP is the inverse of the house edge
rtp(2.7); // 97.3

// Expected loss over a number of bets
expectedLoss(10, 1000, 2.7); // 270

API

| Function | Description | |---|---| | diceEdge(chance, payout) | House edge (%) from win chance (%) and payout multiplier | | crashEdge(commission) | House edge (%) of a crash/limbo game from its commission (%) | | rouletteEdge(zeros, slots) | House edge (%) from the number of zero pockets and total pockets | | blackjackEdge({ decks, h17, blackjackPays }) | Approximate house edge (%) from the rule set (8 decks / S17 / 3:2 by default) | | rtp(edge) | Return to player (%), 100 - edge | | expectedLoss(bet, bets, edge) | Expected loss over a number of bets at a given edge |

Formulas

dice edge       = (1 - payout / fairPayout) × 100, fairPayout = 1 / (chance / 100)
crash edge      = commission %
roulette edge   = zeros / slots × 100
blackjack edge  = 0.46 base (8 decks, S17, 3:2) ± deck/rule adjustments
rtp             = 100 - edge
expected loss   = bet × number of bets × edge / 100

Blackjack figures are widely-used approximations for basic strategy, not exact combinatorial results — actual edge depends on the full rule set (surrender, doubling restrictions, etc.).

Outils associés

Outils gratuits et open source, utilisables dans le navigateur, par la même équipe :

• Calculateur d'Avantage de la Maison — cette bibliothèque, en version web
• Convertisseur de Cotes — cotes décimales, fractionnaires et américaines

License

MIT — see LICENSE.