diff --git a/apps/web/src/components/game/AdventurerPanel.tsx b/apps/web/src/components/game/AdventurerPanel.tsx
index e7ae9ea..2ae128b 100644
--- a/apps/web/src/components/game/AdventurerPanel.tsx
+++ b/apps/web/src/components/game/AdventurerPanel.tsx
@@ -19,9 +19,10 @@ interface AdventurerCardProps {
   adventurer: Adventurer;
   currentGold: number;
   unlockHint?: string | undefined;
+  formatNumber: (n: number) => string;
 }
 
-const AdventurerCard = ({ adventurer, currentGold, unlockHint }: AdventurerCardProps): React.JSX.Element => {
+const AdventurerCard = ({ adventurer, currentGold, unlockHint, formatNumber }: AdventurerCardProps): React.JSX.Element => {
   const { buyAdventurer } = useGame();
   const cost = adventurerCost(adventurer);
   const canAfford = currentGold >= cost;
@@ -31,9 +32,9 @@ const AdventurerCard = ({ adventurer, currentGold, unlockHint }: AdventurerCardP
       <div className="adventurer-icon">{CLASS_ICONS[adventurer.class] ?? "⚔️"}</div>
       <div className="adventurer-info">
         <h3>{adventurer.name}</h3>
-        <p>{adventurer.goldPerSecond.toFixed(2)} gold/s each</p>
+        <p>{formatNumber(adventurer.goldPerSecond)} gold/s each</p>
         {adventurer.essencePerSecond > 0 && (
-          <p>{adventurer.essencePerSecond.toFixed(3)} essence/s each</p>
+          <p>{formatNumber(adventurer.essencePerSecond)} essence/s each</p>
         )}
       </div>
       <div className="adventurer-count">×{adventurer.count}</div>
@@ -43,7 +44,7 @@ const AdventurerCard = ({ adventurer, currentGold, unlockHint }: AdventurerCardP
         onClick={() => { buyAdventurer(adventurer.id); }}
         type="button"
       >
-        {adventurer.unlocked ? `🪙 ${cost}` : "🔒 Locked"}
+        {adventurer.unlocked ? `🪙 ${formatNumber(cost)}` : "🔒 Locked"}
       </button>
       {!adventurer.unlocked && unlockHint && (
         <p className="unlock-hint">📜 Complete: {unlockHint}</p>
@@ -53,7 +54,7 @@ const AdventurerCard = ({ adventurer, currentGold, unlockHint }: AdventurerCardP
 };
 
 export const AdventurerPanel = (): React.JSX.Element => {
-  const { state } = useGame();
+  const { state, formatNumber } = useGame();
   const [showLocked, setShowLocked] = useState(true);
 
   if (!state) return <section className="panel"><p>Loading...</p></section>;
@@ -87,6 +88,7 @@ export const AdventurerPanel = (): React.JSX.Element => {
             adventurer={adventurer}
             currentGold={state.resources.gold}
             unlockHint={adventurerUnlockHints.get(adventurer.id)}
+            formatNumber={formatNumber}
           />
         ))}
       </div>
diff --git a/apps/web/src/components/game/PrestigePanel.tsx b/apps/web/src/components/game/PrestigePanel.tsx
index 8fa891c..87ad443 100644
--- a/apps/web/src/components/game/PrestigePanel.tsx
+++ b/apps/web/src/components/game/PrestigePanel.tsx
@@ -5,7 +5,7 @@ import { useGame } from "../../context/GameContext.js";
 const PRESTIGE_THRESHOLD = 1_000_000;
 
 export const PrestigePanel = (): React.JSX.Element => {
-  const { state, reload } = useGame();
+  const { state, reload, formatNumber } = useGame();
   const [characterName, setCharacterName] = useState("");
   const [isPending, setIsPending] = useState(false);
   const [result, setResult] = useState<{ runestones: number; count: number } | null>(null);
@@ -42,10 +42,10 @@ export const PrestigePanel = (): React.JSX.Element => {
       <div className="prestige-status">
         <p>
           Total gold earned:{" "}
-          <strong>{state.player.totalGoldEarned.toLocaleString()}</strong>
+          <strong>{formatNumber(state.player.totalGoldEarned)}</strong>
         </p>
         <p>
-          Required: <strong>{PRESTIGE_THRESHOLD.toLocaleString()}</strong>
+          Required: <strong>{formatNumber(PRESTIGE_THRESHOLD)}</strong>
         </p>
         <p>Current prestige count: <strong>{state.prestige.count}</strong></p>
         <p>
@@ -82,7 +82,7 @@ export const PrestigePanel = (): React.JSX.Element => {
         </div>
       ) : (
         <p className="prestige-locked">
-          Earn {(PRESTIGE_THRESHOLD - state.player.totalGoldEarned).toLocaleString()} more
+          Earn {formatNumber(PRESTIGE_THRESHOLD - state.player.totalGoldEarned)} more
           gold to unlock prestige.
         </p>
       )}
diff --git a/apps/web/src/components/game/UpgradePanel.tsx b/apps/web/src/components/game/UpgradePanel.tsx
index dc8efb0..a9f7944 100644
--- a/apps/web/src/components/game/UpgradePanel.tsx
+++ b/apps/web/src/components/game/UpgradePanel.tsx
@@ -9,9 +9,10 @@ interface UpgradeCardProps {
   currentEssence: number;
   currentCrystals: number;
   unlockHint?: string | undefined;
+  formatNumber: (n: number) => string;
 }
 
-const UpgradeCard = ({ upgrade, currentGold, currentEssence, currentCrystals, unlockHint }: UpgradeCardProps): React.JSX.Element => {
+const UpgradeCard = ({ upgrade, currentGold, currentEssence, currentCrystals, unlockHint, formatNumber }: UpgradeCardProps): React.JSX.Element => {
   const { buyUpgrade } = useGame();
   const canAfford =
     currentGold >= upgrade.costGold &&
@@ -27,9 +28,9 @@ const UpgradeCard = ({ upgrade, currentGold, currentEssence, currentCrystals, un
           <p className="upgrade-multiplier">×{upgrade.multiplier} multiplier</p>
         </div>
         <div className="upgrade-cost">
-          {upgrade.costGold > 0 && <span>🪙 {upgrade.costGold.toLocaleString()}</span>}
-          {upgrade.costEssence > 0 && <span>✨ {upgrade.costEssence.toLocaleString()}</span>}
-          {(upgrade.costCrystals ?? 0) > 0 && <span>💎 {upgrade.costCrystals?.toLocaleString()}</span>}
+          {upgrade.costGold > 0 && <span>🪙 {formatNumber(upgrade.costGold)}</span>}
+          {upgrade.costEssence > 0 && <span>✨ {formatNumber(upgrade.costEssence)}</span>}
+          {(upgrade.costCrystals ?? 0) > 0 && <span>💎 {formatNumber(upgrade.costCrystals ?? 0)}</span>}
         </div>
         <span className="upgrade-locked-label">Locked</span>
         {unlockHint && <p className="unlock-hint">{unlockHint}</p>}
@@ -54,9 +55,9 @@ const UpgradeCard = ({ upgrade, currentGold, currentEssence, currentCrystals, un
         <p className="upgrade-multiplier">×{upgrade.multiplier} multiplier</p>
       </div>
       <div className="upgrade-cost">
-        {upgrade.costGold > 0 && <span>🪙 {upgrade.costGold.toLocaleString()}</span>}
-        {upgrade.costEssence > 0 && <span>✨ {upgrade.costEssence.toLocaleString()}</span>}
-        {(upgrade.costCrystals ?? 0) > 0 && <span>💎 {upgrade.costCrystals?.toLocaleString()}</span>}
+        {upgrade.costGold > 0 && <span>🪙 {formatNumber(upgrade.costGold)}</span>}
+        {upgrade.costEssence > 0 && <span>✨ {formatNumber(upgrade.costEssence)}</span>}
+        {(upgrade.costCrystals ?? 0) > 0 && <span>💎 {formatNumber(upgrade.costCrystals ?? 0)}</span>}
       </div>
       <button
         className="buy-button"
@@ -71,7 +72,7 @@ const UpgradeCard = ({ upgrade, currentGold, currentEssence, currentCrystals, un
 };
 
 export const UpgradePanel = (): React.JSX.Element => {
-  const { state } = useGame();
+  const { state, formatNumber } = useGame();
   const [showLocked, setShowLocked] = useState(true);
 
   if (!state) return <section className="panel"><p>Loading...</p></section>;
@@ -116,6 +117,7 @@ export const UpgradePanel = (): React.JSX.Element => {
               currentGold={state.resources.gold}
               currentEssence={state.resources.essence}
               currentCrystals={state.resources.crystals}
+              formatNumber={formatNumber}
             />
           ))}
           {purchased.map((upgrade) => (
@@ -125,6 +127,7 @@ export const UpgradePanel = (): React.JSX.Element => {
               currentGold={state.resources.gold}
               currentEssence={state.resources.essence}
               currentCrystals={state.resources.crystals}
+              formatNumber={formatNumber}
             />
           ))}
           {showLocked && locked.map((upgrade) => (
@@ -134,6 +137,7 @@ export const UpgradePanel = (): React.JSX.Element => {
               currentGold={state.resources.gold}
               currentEssence={state.resources.essence}
               currentCrystals={state.resources.crystals}
+              formatNumber={formatNumber}
               unlockHint={upgradeUnlockHints.get(upgrade.id)}
             />
           ))}