diff --git a/AK/FloatingPointStringConversions.cpp b/AK/FloatingPointStringConversions.cpp
index 0dfddd1746..202d09c928 100644
--- a/AK/FloatingPointStringConversions.cpp
+++ b/AK/FloatingPointStringConversions.cpp
@@ -1227,14 +1227,7 @@ static i32 decimal_exponent_to_binary_exponent(i32 exponent)
 
 static u128 multiply(u64 a, u64 b)
 {
-#ifdef __SIZEOF_INT128__
-    unsigned __int128 result = (unsigned __int128)a * b;
-    u64 low = result;
-    u64 high = result >> 64;
-    return u128 { low, high };
-#else
-    return u128 { a }.wide_multiply(u128 { b }).low;
-#endif
+    return UFixedBigInt<64>(a).wide_multiply(b);
 }
 
 template<unsigned Precision>
@@ -1249,10 +1242,7 @@ u128 multiplication_approximation(u64 value, i32 exponent)
 
     if ((lower_result.high() & mask) == mask) {
         auto upper_result = multiply(z.low(), value);
-        lower_result.low() += upper_result.high();
-        if (upper_result.high() > lower_result.low()) {
-            ++lower_result.high();
-        }
+        lower_result += upper_result.high();
     }
 
     return lower_result;
diff --git a/AK/StringFloatingPointConversions.cpp b/AK/StringFloatingPointConversions.cpp
index ad04bce760..85f3c8358b 100644
--- a/AK/StringFloatingPointConversions.cpp
+++ b/AK/StringFloatingPointConversions.cpp
@@ -171,25 +171,14 @@ FloatingPointExponentialForm inner_convert_floating_point_to_decimal_exponential
 
 static u128 multiply(u64 a, u64 b)
 {
-#ifdef __SIZEOF_INT128__
-    unsigned __int128 result = (unsigned __int128)a * b;
-    u64 low = result;
-    u64 high = result >> 64;
-    return u128 { low, high };
-#else
-    return u128 { a }.wide_multiply(u128 { b }).low;
-#endif
+    return UFixedBigInt<64>(a).wide_multiply(b);
 }
 
 template<>
 FloatingPointExponentialForm convert_floating_point_to_decimal_exponential_form<float>(float value)
 {
     auto multiply_and_shift = [](u64 operand, u64 multiplier, i32 shift) {
-#ifdef __SIZEOF_INT128__
-        auto result = (unsigned __int128)operand * multiplier;
-#else
         auto result = multiply(operand, multiplier);
-#endif
         if (shift < 0)
             return static_cast<u64>(result << static_cast<u32>(-shift));
         else
diff --git a/Userland/Libraries/LibCrypto/Curves/SECP256r1.cpp b/Userland/Libraries/LibCrypto/Curves/SECP256r1.cpp
index f647c07c1b..91ff20a00a 100644
--- a/Userland/Libraries/LibCrypto/Curves/SECP256r1.cpp
+++ b/Userland/Libraries/LibCrypto/Curves/SECP256r1.cpp
@@ -57,8 +57,7 @@ static u256 select(u256 const& left, u256 const& right, bool condition)
 
 static u512 multiply(u256 const& left, u256 const& right)
 {
-    auto result = left.wide_multiply(right);
-    return { result.low, result.high };
+    return left.wide_multiply(right);
 }
 
 static u256 modular_reduce(u256 const& value)