diff --git a/src/lib/dice.ts b/src/lib/dice.ts
index 26afc1c..3d629a9 100644
--- a/src/lib/dice.ts
+++ b/src/lib/dice.ts
@@ -45,7 +45,7 @@ export function formatSummary(rolls: number[], discarded: number[], diceType: Di
       if (!kept) formatted = `~~${formatted}~~`;
       return formatted;
     })
-    .join(' ');
+    .join(', ');
 }
 
 export function parseExpression(input: string): RollResult | RollResult[] {