diff --git a/PKHeX.Core/Util/Util.cs b/PKHeX.Core/Util/Util.cs
index b8a71b330..c87e43906 100644
--- a/PKHeX.Core/Util/Util.cs
+++ b/PKHeX.Core/Util/Util.cs
@@ -123,15 +123,20 @@ namespace PKHeX.Core
 
         public static byte[] GetBytesFromHexString(string seed)
         {
-            return Enumerable.Range(0, seed.Length)
-                .Where(x => x % 2 == 0)
-                .Select(x => Convert.ToByte(seed.Substring(x, 2), 16))
-                .Reverse().ToArray();
+            byte[] result = new byte[seed.Length / 2];
+            for (int i = 0; i < result.Length; i++)
+            {
+                var slice = seed.Substring(i * 2, 2);
+                result[i] = Convert.ToByte(slice, 16);
+            }
+            Array.Reverse(result);
+            return result;
         }
 
         public static string GetHexStringFromBytes(byte[] data, int offset, int length)
         {
-            data = data.Skip(offset).Take(length).Reverse().ToArray();
+            data = data.Slice(offset, length);
+            Array.Reverse(data);
             return BitConverter.ToString(data).Replace("-", string.Empty);
         }
 
diff --git a/Tests/PKHeX.Core.Tests/PKM/StringTests.cs b/Tests/PKHeX.Core.Tests/PKM/StringTests.cs
index 32b5710d9..b07a76e08 100644
--- a/Tests/PKHeX.Core.Tests/PKM/StringTests.cs
+++ b/Tests/PKHeX.Core.Tests/PKM/StringTests.cs
@@ -49,12 +49,11 @@ namespace PKHeX.Tests.PKM
             CheckStringGetSet(nameof(pkm.Nickname), name_nidoran, pkm.Nickname, byte_nidoran, pkm.Nickname_Trash);
         }
 
-        private static void CheckStringGetSet(string check, string instr, string outstr, byte[] indata,
-            byte[] outdata)
+        private static void CheckStringGetSet(string check, string instr, string outstr, byte[] indata, byte[] outdata)
         {
             instr.Should().BeEquivalentTo(outstr);
 
-            outdata = outdata.Take(indata.Length).ToArray();
+            outdata = outdata[..indata.Length];
 
             indata.SequenceEqual(outdata).Should()
                 .BeTrue($"expected {check} to set properly, instead got {string.Join(", ", outdata.Select(z => $"{z:X2}"))}");
diff --git a/Tests/PKHeX.Core.Tests/Util/ConvertUtilTests.cs b/Tests/PKHeX.Core.Tests/Util/ConvertUtilTests.cs
index 8a235aa95..f1a935054 100644
--- a/Tests/PKHeX.Core.Tests/Util/ConvertUtilTests.cs
+++ b/Tests/PKHeX.Core.Tests/Util/ConvertUtilTests.cs
@@ -1,4 +1,5 @@
-using FluentAssertions;
+using System;
+using FluentAssertions;
 using Xunit;
 
 namespace PKHeX.Tests.Util
@@ -34,5 +35,14 @@ namespace PKHeX.Tests.Util
             var convert = Core.Util.GetHexValue(v);
             convert.Should().Be(result);
         }
+
+        [Theory]
+        [InlineData("01020304", 0x1020304)]
+        public void CheckConvertHexString(string v, uint result)
+        {
+            var convert = Core.Util.GetBytesFromHexString(v);
+            var u32 = BitConverter.ToUInt32(convert);
+            u32.Should().Be(result);
+        }
     }
 }