diff --git a/src/tests/chain_context_tests.rs b/src/tests/chain_context_tests.rs
index a7254e3..b9a5d10 100644
--- a/src/tests/chain_context_tests.rs
+++ b/src/tests/chain_context_tests.rs
@@ -260,8 +260,8 @@ mod tests {
         runtime
             .call(&solidity_selector("test_prevrandao()"), &[])
             .unwrap();
-        // DEFAULT_PREVRANDAO: 0000000000000000000000000505050505050505050505050505050505050505
-        runtime.assert_result("0000000000000000000000000505050505050505050505050505050505050505");
+        // DEFAULT_PREVRANDAO: 0505050505050505050505050505050505050505050505050505050505050505
+        runtime.assert_result("0505050505050505050505050505050505050505050505050505050505050505");
     }
 
     #[test]
@@ -292,8 +292,8 @@ mod tests {
         runtime
             .call(&solidity_selector("test_difficulty()"), &[])
             .unwrap();
-        // DEFAULT_PREVRANDAO: 0000000000000000000000000505050505050505050505050505050505050505
-        runtime.assert_result("0000000000000000000000000505050505050505050505050505050505050505");
+        // DEFAULT_PREVRANDAO: 0505050505050505050505050505050505050505050505050505050505050505
+        runtime.assert_result("0505050505050505050505050505050505050505050505050505050505050505");
     }
 
     #[test]
diff --git a/stdlib/chain.c b/stdlib/chain.c
index 327c232..e80727e 100644
--- a/stdlib/chain.c
+++ b/stdlib/chain.c
@@ -191,8 +191,7 @@ void wrapper_block_coin_base(bytes32 *result) {
 }
 
 void wrapper_block_prevRandao(bytes32 *result) {
-  getBlockPrevRandao(12 + (ADDRESS_UINT)result); // 32 bytes
-  clear_first_12_bytes(result);
+  getBlockPrevRandao((ADDRESS_UINT)result); // 32 bytes
 }
 
 void wrapper_callvalue(uint256_t *result) {