diff --git a/mulxp_hash.hpp b/mulxp_hash.hpp
index 77a7952..818f276 100644
--- a/mulxp_hash.hpp
+++ b/mulxp_hash.hpp
@@ -277,12 +277,12 @@ inline std::uint64_t mul32( std::uint32_t x, std::uint32_t y )
     return (std::uint64_t)x * y;
 }
 
-inline std::uint32_t mulxp1_hash32( unsigned char const * p, std::size_t n, std::uint32_t seed )
+inline std::uint32_t mulxp1_hash32( unsigned char const * p, std::size_t n, std::uint64_t seed )
 {
     std::uint32_t const q = 0x9e3779b9U;
     std::uint32_t const k = q * q;
 
-    std::uint64_t h = mul32( seed + q, k );
+    std::uint64_t h = ( seed + q ) * k;
     std::uint32_t w = (std::uint32_t)h;
 
     h ^= n;
@@ -319,12 +319,12 @@ inline std::uint32_t mulxp1_hash32( unsigned char const * p, std::size_t n, std:
     return (std::uint32_t)h ^ (std::uint32_t)(h >> 32);
 }
 
-inline std::uint32_t mulxp3_hash32( unsigned char const * p, std::size_t n, std::uint32_t seed )
+inline std::uint32_t mulxp3_hash32( unsigned char const * p, std::size_t n, std::uint64_t seed )
 {
     std::uint32_t const q = 0x9e3779b9U;
     std::uint32_t const k = q * q;
 
-    std::uint64_t h = mul32( seed + q, k );
+    std::uint64_t h = ( seed + q ) * k;
     std::uint32_t w = (std::uint32_t)h;
 
     h ^= n;