diff --git a/src/input.ts b/src/input.ts
index 6b5ff13b..a7469b4f 100644
--- a/src/input.ts
+++ b/src/input.ts
@@ -202,10 +202,10 @@ export const Key = {
 
 // NOTE: This must match the definition in input.rs.
 export const Button = {
-  Up: 0,
-  Down: 1,
-  Left: 2,
-  Right: 3,
+  Up: core.BUTTON_UP,
+  Down: core.BUTTON_DOWN,
+  Left: core.BUTTON_LEFT,
+  Right: core.BUTTON_RIGHT,
 } as const;
 type Button = (typeof Button)[keyof typeof Button];
 
diff --git a/src/script/input.rs b/src/script/input.rs
index ed5fa013..cbb04675 100644
--- a/src/script/input.rs
+++ b/src/script/input.rs
@@ -122,6 +122,10 @@ impl InputAPI {
                 ctx.new_fn(move |_ctx: &ContextRef, b: u32| input.btn(b))?,
             )?;
         }
+        builder.export("BUTTON_UP", ctx.new_u32(Button::Up)?)?;
+        builder.export("BUTTON_DOWN", ctx.new_u32(Button::Down)?)?;
+        builder.export("BUTTON_LEFT", ctx.new_u32(Button::Left)?)?;
+        builder.export("BUTTON_RIGHT", ctx.new_u32(Button::Right)?)?;
         builder.build("input-core")?;
         Ok(InputAPI { input })
     }
diff --git a/types/input-core.d.ts b/types/input-core.d.ts
index 027ccf81..d6d0b905 100644
--- a/types/input-core.d.ts
+++ b/types/input-core.d.ts
@@ -1,3 +1,8 @@
 // These are the functions exposed by the native input module.
 //
+export const BUTTON_UP: number;
+export const BUTTON_DOWN: number;
+export const BUTTON_LEFT: number;
+export const BUTTON_RIGHT: number;
+
 export function btn(b: number): boolean;