diff --git a/src/Game.tsx b/src/Game.tsx
index 79e30bb..9786b7f 100644
--- a/src/Game.tsx
+++ b/src/Game.tsx
@@ -54,8 +54,10 @@ function Game(props: GameProps) {
       return;
     }
     if (guesses.length === props.maxGuesses) return;
-    if (/^[a-z]$/.test(key)) {
-      setCurrentGuess((guess) => (guess + key).slice(0, wordLength));
+    if (/^[a-z]$/i.test(key)) {
+      setCurrentGuess((guess) =>
+        (guess + key.toLowerCase()).slice(0, wordLength)
+      );
       setHint("");
       setSrStatus("");
     } else if (key === "Backspace") {