diff --git a/ethcore/src/ethereum/ethash.rs b/ethcore/src/ethereum/ethash.rs
index f58e47036..764a74bfe 100644
--- a/ethcore/src/ethereum/ethash.rs
+++ b/ethcore/src/ethereum/ethash.rs
@@ -374,13 +374,13 @@ mod tests {
 		let vm_factory = Default::default();
 		let mut b = OpenBlock::new(engine.deref(), &vm_factory, Default::default(), false, db, &genesis_header, last_hashes, Address::zero(), (3141562.into(), 31415620.into()), vec![]).unwrap();
 		let mut uncle = Header::new();
-		let uncle_author: Address = "ef2d6d194084c2de36e0dabfce45d046b37d1106".parse().unwrap();
+		let uncle_author: Address = "ef2d6d194084c2de36e0dabfce45d046b37d1106".into();
 		uncle.author = uncle_author.clone();
 		b.push_uncle(uncle).unwrap();
 
 		let b = b.close();
-		assert_eq!(b.state().balance(&Address::zero()), U256::from_str("478eae0e571ba000").unwrap());
-		assert_eq!(b.state().balance(&uncle_author), U256::from_str("3cb71f51fc558000").unwrap());
+		assert_eq!(b.state().balance(&Address::zero()), "478eae0e571ba000".into());
+		assert_eq!(b.state().balance(&uncle_author), "3cb71f51fc558000".into());
 	}
 
 	#[test]
diff --git a/ethcore/src/ethereum/mod.rs b/ethcore/src/ethereum/mod.rs
index b0f8ed26f..40e85d619 100644
--- a/ethcore/src/ethereum/mod.rs
+++ b/ethcore/src/ethereum/mod.rs
@@ -69,21 +69,21 @@ mod tests {
 		let mut db = db_result.take();
 		spec.ensure_db_good(db.as_hashdb_mut()).unwrap();
 		let s = State::from_existing(db, genesis_header.state_root.clone(), engine.account_start_nonce(), Default::default()).unwrap();
-		assert_eq!(s.balance(&"0000000000000000000000000000000000000001".parse().unwrap()), U256::from(1u64));
-		assert_eq!(s.balance(&"0000000000000000000000000000000000000002".parse().unwrap()), U256::from(1u64));
-		assert_eq!(s.balance(&"0000000000000000000000000000000000000003".parse().unwrap()), U256::from(1u64));
-		assert_eq!(s.balance(&"0000000000000000000000000000000000000004".parse().unwrap()), U256::from(1u64));
-		assert_eq!(s.balance(&"102e61f5d8f9bc71d0ad4a084df4e65e05ce0e1c".parse().unwrap()), U256::from(1u64) << 200);
-		assert_eq!(s.balance(&"0000000000000000000000000000000000000000".parse().unwrap()), U256::from(0u64));
+		assert_eq!(s.balance(&"0000000000000000000000000000000000000001".into()), 1u64.into());
+		assert_eq!(s.balance(&"0000000000000000000000000000000000000002".into()), 1u64.into());
+		assert_eq!(s.balance(&"0000000000000000000000000000000000000003".into()), 1u64.into());
+		assert_eq!(s.balance(&"0000000000000000000000000000000000000004".into()), 1u64.into());
+		assert_eq!(s.balance(&"102e61f5d8f9bc71d0ad4a084df4e65e05ce0e1c".into()), U256::from(1u64) << 200);
+		assert_eq!(s.balance(&"0000000000000000000000000000000000000000".into()), 0u64.into());
 	}
 
 	#[test]
 	fn morden() {
 		let morden = new_morden();
 
-		assert_eq!(morden.state_root(), H256::from_str("f3f4696bbf3b3b07775128eb7a3763279a394e382130f27c21e70233e04946a9").unwrap());
+		assert_eq!(morden.state_root(), "f3f4696bbf3b3b07775128eb7a3763279a394e382130f27c21e70233e04946a9".into());
 		let genesis = morden.genesis_block();
-		assert_eq!(BlockView::new(&genesis).header_view().sha3(), H256::from_str("0cd786a2425d16f152c658316c423e6ce1181e15c3295826d7c9904cba9ce303").unwrap());
+		assert_eq!(BlockView::new(&genesis).header_view().sha3(), "0cd786a2425d16f152c658316c423e6ce1181e15c3295826d7c9904cba9ce303".into());
 
 		let _ = morden.engine;
 	}
@@ -92,9 +92,9 @@ mod tests {
 	fn frontier() {
 		let frontier = new_frontier();
 
-		assert_eq!(frontier.state_root(), H256::from_str("d7f8974fb5ac78d9ac099b9ad5018bedc2ce0a72dad1827a1709da30580f0544").unwrap());
+		assert_eq!(frontier.state_root(), "d7f8974fb5ac78d9ac099b9ad5018bedc2ce0a72dad1827a1709da30580f0544".into());
 		let genesis = frontier.genesis_block();
-		assert_eq!(BlockView::new(&genesis).header_view().sha3(), H256::from_str("d4e56740f876aef8c010b86a40d5f56745a118d0906a34e69aec8c0db1cb8fa3").unwrap());
+		assert_eq!(BlockView::new(&genesis).header_view().sha3(), "d4e56740f876aef8c010b86a40d5f56745a118d0906a34e69aec8c0db1cb8fa3".into());
 
 		let _ = frontier.engine;
 	}
diff --git a/ethcore/src/types/transaction.rs b/ethcore/src/types/transaction.rs
index 8c26293d3..e9cc2211c 100644
--- a/ethcore/src/types/transaction.rs
+++ b/ethcore/src/types/transaction.rs
@@ -361,10 +361,10 @@ fn sender_test() {
 	assert_eq!(t.gas_price, U256::from(0x01u64));
 	assert_eq!(t.nonce, U256::from(0x00u64));
 	if let Action::Call(ref to) = t.action {
-		assert_eq!(*to, "095e7baea6a6c7c4c2dfeb977efac326af552d87".parse().unwrap());
+		assert_eq!(*to, "095e7baea6a6c7c4c2dfeb977efac326af552d87".into());
 	} else { panic!(); }
 	assert_eq!(t.value, U256::from(0x0au64));
-	assert_eq!(t.sender().unwrap(), "0f65fe9276bc9a24ae7083ae28e2660ef72df99e".parse().unwrap());
+	assert_eq!(t.sender().unwrap(), "0f65fe9276bc9a24ae7083ae28e2660ef72df99e".into());
 }
 
 #[test]
diff --git a/util/bigint/src/uint.rs b/util/bigint/src/uint.rs
index 172e09c70..d66caf3c1 100644
--- a/util/bigint/src/uint.rs
+++ b/util/bigint/src/uint.rs
@@ -1129,6 +1129,12 @@ macro_rules! construct_uint {
 				Ok(())
 			}
 		}
+
+		impl From<&'static str> for $name {
+			fn from(s: &'static str) -> Self {
+				s.parse().unwrap()
+			}
+		}
 	);
 }
 
diff --git a/util/src/bloom.rs b/util/src/bloom.rs
index a67f8d482..779419d44 100644
--- a/util/src/bloom.rs
+++ b/util/src/bloom.rs
@@ -124,9 +124,9 @@ mod tests {
 
 	#[test]
 	fn shift_bloomed() {
-		let bloom: H2048 = "00000000000000000000000000000000000000001000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000002020000000000000000000000000000000000000000000008000000001000000000000000000000000000000000000000000000000000001000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000".parse().unwrap();
-		let address: Address = "ef2d6d194084c2de36e0dabfce45d046b37d1106".parse().unwrap();
-		let topic: H256 = "02c69be41d0b7e40352fc85be1cd65eb03d40ef8427a0ca4596b1ead9a00e9fc".parse().unwrap();
+		let bloom: H2048 = "00000000000000000000000000000000000000001000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000002020000000000000000000000000000000000000000000008000000001000000000000000000000000000000000000000000000000000001000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000".into();
+		let address: Address = "ef2d6d194084c2de36e0dabfce45d046b37d1106".into();
+		let topic: H256 = "02c69be41d0b7e40352fc85be1cd65eb03d40ef8427a0ca4596b1ead9a00e9fc".into();
 
 		let mut my_bloom = H2048::default();
 		assert!(!my_bloom.contains_bloomed(&address.sha3()));