diff --git a/YapDatabase/Utilities/YapMurmurHash.h b/YapDatabase/Utilities/YapMurmurHash.h
index 4444613..be8f82c 100644
--- a/YapDatabase/Utilities/YapMurmurHash.h
+++ b/YapDatabase/Utilities/YapMurmurHash.h
@@ -14,7 +14,7 @@ NSUInteger YapMurmurHash3(NSUInteger hash1, NSUInteger hash2, NSUInteger hash3);
 
 NSUInteger YapMurmurHashData(NSData *data);
 
-int32_t YapMurmurHashData_32(NSData *data);
-int64_t YapMurmurHashData_64(NSData *data);
+uint32_t YapMurmurHashData_32(NSData *data);
+uint64_t YapMurmurHashData_64(NSData *data);
 
 #endif
diff --git a/YapDatabase/Utilities/YapMurmurHash.m b/YapDatabase/Utilities/YapMurmurHash.m
index c3a8ef4..d16c0ff 100644
--- a/YapDatabase/Utilities/YapMurmurHash.m
+++ b/YapDatabase/Utilities/YapMurmurHash.m
@@ -275,7 +275,7 @@ NSUInteger YapMurmurHashData(NSData *inData)
 	}
 }
 
-int32_t YapMurmurHashData_32(NSData *inData)
+uint32_t YapMurmurHashData_32(NSData *inData)
 {
 	// MurmurHash2 (32-bit)
 	//
@@ -333,10 +333,10 @@ int32_t YapMurmurHashData_32(NSData *inData)
 	h *= m;
 	h ^= h >> 15;
 	
-	return (int32_t)h;
+	return h;
 }
 
-int64_t YapMurmurHashData_64(NSData *inData)
+uint64_t YapMurmurHashData_64(NSData *inData)
 {
 	// MurmurHash2 (64-bit)
 	//
@@ -399,5 +399,5 @@ int64_t YapMurmurHashData_64(NSData *inData)
 	h *= m;
 	h ^= h >> r;
 	
-	return (int64_t)h;
+	return h;
 }