diff --git a/jsval.rs b/jsval.rs
index 427cc284e..aed5e064f 100644
--- a/jsval.rs
+++ b/jsval.rs
@@ -230,6 +230,16 @@ impl JSVal {
         self.is_null() || self.is_undefined()
     }
 
+    #[cfg(target_word_size = "64")]
+    pub fn is_boolean(&self) -> bool {
+        self.v == JSVAL_SHIFTED_TAG_BOOLEAN as u64
+    }
+
+    #[cfg(target_word_size = "32")]
+    pub fn is_boolean(&self) -> bool {
+        (self.v >> 32) == JSVAL_TAG_BOOLEAN as u64
+    }
+
     #[cfg(target_word_size = "64")]
     pub fn is_double(&self) -> bool {
         self.v <= JSVAL_SHIFTED_TAG_MAX_DOUBLE as u64
@@ -273,6 +283,17 @@ impl JSVal {
         (self.v >> 32) == JSVAL_TAG_OBJECT as u64
     }
 
+    #[cfg(target_word_size = "64")]
+    pub fn to_boolean(&self) -> bool {
+        assert!(self.is_boolean());
+        (self.v & JSVAL_PAYLOAD_MASK) != 0
+    }
+
+    #[cfg(target_word_size = "32")]
+    pub fn to_boolean(&self) -> bool {
+        (self.v & 0x00000000FFFFFFFF) != 0
+    }
+
     pub fn to_object(&self) -> *mut JSObject {
         assert!(self.is_object());
         self.to_object_or_null()