diff --git a/ui/inputbox.c b/ui/inputbox.c
new file mode 100644
index 0000000..91a1444
--- /dev/null
+++ b/ui/inputbox.c
@@ -0,0 +1,32 @@
+/* Copyright 2023 Dual Tachyon
+ * https://github.com/DualTachyon
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *     Unless required by applicable law or agreed to in writing, software
+ *     distributed under the License is distributed on an "AS IS" BASIS,
+ *     WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *     See the License for the specific language governing permissions and
+ *     limitations under the License.
+ */
+
+#include <string.h>
+#include "ui/inputbox.h"
+
+char gInputBox[8];
+uint8_t gInputBoxIndex;
+
+void INPUTBOX_Append(char Digit)
+{
+	if (gInputBoxIndex == 0) {
+		memset(gInputBox, 10, sizeof(gInputBox));
+	} else if (gInputBoxIndex >= sizeof(gInputBox)) {
+		return;
+	}
+	gInputBox[gInputBoxIndex++] = Digit;
+}
+
diff --git a/ui/inputbox.h b/ui/inputbox.h
new file mode 100644
index 0000000..66026f2
--- /dev/null
+++ b/ui/inputbox.h
@@ -0,0 +1,28 @@
+/* Copyright 2023 Dual Tachyon
+ * https://github.com/DualTachyon
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *     Unless required by applicable law or agreed to in writing, software
+ *     distributed under the License is distributed on an "AS IS" BASIS,
+ *     WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *     See the License for the specific language governing permissions and
+ *     limitations under the License.
+ */
+
+#ifndef UI_INPUTBOX_H
+#define UI_INPUTBOX_H
+
+#include <stdint.h>
+
+extern char gInputBox[8];
+extern uint8_t gInputBoxIndex;
+
+void INPUTBOX_Append(char Digit);
+
+#endif
+