diff --git a/website/src/lib/components/self/games/Mines.svelte b/website/src/lib/components/self/games/Mines.svelte
index 7348ca8..17b0aaa 100644
--- a/website/src/lib/components/self/games/Mines.svelte
+++ b/website/src/lib/components/self/games/Mines.svelte
@@ -16,6 +16,7 @@
 	import { onMount, onDestroy } from 'svelte';
 	import { ModeWatcher } from 'mode-watcher';
 	import { fetchPortfolioSummary } from '$lib/stores/portfolio-data';
+	import { calculateMinesMultiplier } from '$lib/utils';
 
 	const GRID_SIZE = 5;
 	const TOTAL_TILES = GRID_SIZE * GRID_SIZE;
@@ -59,14 +60,6 @@
 		return (probability * 100).toFixed(2);
 	}
 
-	function calculateRawMultiplier(picks: number, mines: number): number {
-		let probability = 1;
-		for (let i = 0; i < picks; i++) {
-			probability *= (TOTAL_TILES - mines - i) / (TOTAL_TILES - i);
-		}
-		return probability === 0 ? 1.0 : Math.max(1.0, 1 / probability);
-	}
-
 	function setBetAmount(amount: number) {
 		const clamped = Math.min(amount, Math.min(balance, MAX_BET_AMOUNT));
 		if (clamped >= 0) {
@@ -323,9 +316,7 @@
 					<p class="text-muted-foreground mt-1 text-xs">
 						You will get
 						<span class="text-success font-semibold">
-							{calculateRawMultiplier(isPlaying ? revealedTiles.length + 1 : 1, mineCount).toFixed(
-								2
-							)}x
+							{calculateMinesMultiplier(isPlaying ? revealedTiles.length + 1 : 1, mineCount, betAmount).toFixed(2)}x
 						</span>
 						per tile, probability of winning:
 						<span class="text-success font-semibold">
@@ -417,7 +408,7 @@
 									<span>Next Tile:</span>
 									<span>
 										+{formatValue(
-											betAmount * (calculateRawMultiplier(revealedTiles.length + 1, mineCount) - 1)
+											betAmount * (calculateMinesMultiplier(revealedTiles.length + 1, mineCount, betAmount) - 1)
 										)}
 									</span>
 								</div>
diff --git a/website/src/lib/server/games/mines.ts b/website/src/lib/server/games/mines.ts
index 1b64eda..2acbae4 100644
--- a/website/src/lib/server/games/mines.ts
+++ b/website/src/lib/server/games/mines.ts
@@ -2,6 +2,7 @@ import { db } from '$lib/server/db';
 import { user } from '$lib/server/db/schema';
 import { eq } from 'drizzle-orm';
 import { redis } from '$lib/server/redis';
+import { calculateMinesMultiplier } from '$lib/utils';
 
 interface MinesSession {
     sessionToken: string;
@@ -111,53 +112,6 @@ export async function minesAutoCashout() {
     }
 }
 
-const getMaxPayout = (bet: number, picks: number, mines: number): number => {
-    const MAX_PAYOUT = 2_000_000;
-    const HIGH_BET_THRESHOLD = 50_000;
-
-    const mineFactor = 1 + (mines / 25);
-    const baseMultiplier = (1.4 + Math.pow(picks, 0.45)) * mineFactor;
-
-    if (bet > HIGH_BET_THRESHOLD) {
-        const betRatio = Math.pow(Math.min(1, (bet - HIGH_BET_THRESHOLD) / (MAX_PAYOUT - HIGH_BET_THRESHOLD)), 1);
-
-        // Direct cap on multiplier for high bets
-        const maxAllowedMultiplier = 1.05 + (picks * 0.1);
-        const highBetMultiplier = Math.min(baseMultiplier, maxAllowedMultiplier) * (1 - (bet / MAX_PAYOUT) * 0.9);
-        const betSizeFactor = Math.max(0.1, 1 - (bet / MAX_PAYOUT) * 0.9);
-        const minMultiplier = (1.1 + (picks * 0.15 * betSizeFactor)) * mineFactor;
-
-        const reducedMultiplier = highBetMultiplier - ((highBetMultiplier - minMultiplier) * betRatio);
-        const payout = Math.min(bet * reducedMultiplier, MAX_PAYOUT);
-
-        return payout;
-    }
-
-    const payout = Math.min(bet * baseMultiplier, MAX_PAYOUT);
-    return payout;
-};
-
 export function calculateMultiplier(picks: number, mines: number, betAmount: number): number {
-    const TOTAL_TILES = 25;
-    const HOUSE_EDGE = 0.05;
-
-    // Calculate probability of winning based on picks and mines
-    let probability = 1;
-    for (let i = 0; i < picks; i++) {
-        probability *= (TOTAL_TILES - mines - i) / (TOTAL_TILES - i);
-    }
-
-    if (probability <= 0) return 1.0;
-
-    // Calculate fair multiplier based on probability and house edge
-    const fairMultiplier = (1 / probability) * (1 - HOUSE_EDGE);
-
-    const rawPayout = fairMultiplier * betAmount;
-    const maxPayout = getMaxPayout(betAmount, picks, mines);
-    const cappedPayout = Math.min(rawPayout, maxPayout);
-    const effectiveMultiplier = cappedPayout / betAmount;
-
-    return Math.max(1.0, Number(effectiveMultiplier.toFixed(2)));
-}
-
-
+    return calculateMinesMultiplier(picks, mines, betAmount);
+}
\ No newline at end of file
diff --git a/website/src/lib/utils.ts b/website/src/lib/utils.ts
index 2f131b6..b5cee9c 100644
--- a/website/src/lib/utils.ts
+++ b/website/src/lib/utils.ts
@@ -382,3 +382,38 @@ export function getPrestigeColor(level: number): string {
 export function getMaxPrestigeLevel(): number {
     return 5;
 }
+
+export function calculateMinesMultiplier(picks: number, mines: number, betAmount: number): number {
+    const TOTAL_TILES = 25;
+    const HOUSE_EDGE = 0.05;
+
+    let probability = 1;
+    for (let i = 0; i < picks; i++) {
+        probability *= (TOTAL_TILES - mines - i) / (TOTAL_TILES - i);
+    }
+    if (probability <= 0) return 1.0;
+
+    const fairMultiplier = (1 / probability) * (1 - HOUSE_EDGE);
+
+    // Backend payout cap logic
+    const MAX_PAYOUT = 2_000_000;
+    const HIGH_BET_THRESHOLD = 50_000;
+    const mineFactor = 1 + (mines / 25);
+    const baseMultiplier = (1.4 + Math.pow(picks, 0.45)) * mineFactor;
+    let maxPayout: number;
+    if (betAmount > HIGH_BET_THRESHOLD) {
+        const betRatio = Math.pow(Math.min(1, (betAmount - HIGH_BET_THRESHOLD) / (MAX_PAYOUT - HIGH_BET_THRESHOLD)), 1);
+        const maxAllowedMultiplier = 1.05 + (picks * 0.1);
+        const highBetMultiplier = Math.min(baseMultiplier, maxAllowedMultiplier) * (1 - (betAmount / MAX_PAYOUT) * 0.9);
+        const betSizeFactor = Math.max(0.1, 1 - (betAmount / MAX_PAYOUT) * 0.9);
+        const minMultiplier = (1.1 + (picks * 0.15 * betSizeFactor)) * mineFactor;
+        const reducedMultiplier = highBetMultiplier - ((highBetMultiplier - minMultiplier) * betRatio);
+        maxPayout = Math.min(betAmount * reducedMultiplier, MAX_PAYOUT);
+    } else {
+        maxPayout = Math.min(betAmount * baseMultiplier, MAX_PAYOUT);
+    }
+    const rawPayout = fairMultiplier * betAmount;
+    const cappedPayout = Math.min(rawPayout, maxPayout);
+    const effectiveMultiplier = cappedPayout / betAmount;
+    return Math.max(1.0, Number(effectiveMultiplier.toFixed(2)));
+}