diff --git a/src/Voltaic.Serialization.Etf/Readers/EtfReader.Float.cs b/src/Voltaic.Serialization.Etf/Readers/EtfReader.Float.cs
index cfd2cc3..2ed60b2 100644
--- a/src/Voltaic.Serialization.Etf/Readers/EtfReader.Float.cs
+++ b/src/Voltaic.Serialization.Etf/Readers/EtfReader.Float.cs
@@ -21,11 +21,25 @@ public static bool TryReadSingle(ref ReadOnlySpan<byte> remaining, out float res
             {
                 case EtfTokenType.NewFloat:
                     {
+                        // TODO: Untested, does Discord have any endpoints that accept floats?
                         if (remaining.Length < 8)
                             return false;
-                        //remaining = remaining.Slice(1)
-                        result = MemoryMarshal.Cast<byte, float>(remaining.Slice(1, 8))[0];
-                        remaining = remaining.Slice(9);
+                        remaining = remaining.Slice(1);
+                        Span<double> dst = stackalloc double[1];
+                        var dstBytes = MemoryMarshal.AsBytes(dst);
+
+                        // Swap endian
+                        dstBytes[0] = remaining[7];
+                        dstBytes[1] = remaining[6];
+                        dstBytes[2] = remaining[5];
+                        dstBytes[3] = remaining[4];
+                        dstBytes[4] = remaining[3];
+                        dstBytes[5] = remaining[2];
+                        dstBytes[6] = remaining[1];
+                        dstBytes[7] = remaining[0];
+
+                        result = (float)dst[0];
+                        remaining = remaining.Slice(8);
                         return true;
                     }
                 default:
@@ -48,11 +62,25 @@ public static bool TryReadDouble(ref ReadOnlySpan<byte> remaining, out double re
             {
                 case EtfTokenType.NewFloat:
                     {
+                        // TODO: Untested, does Discord have any endpoints that accept floats?
                         if (remaining.Length < 8)
                             return false;
-                        //remaining = remaining.Slice(1)
-                        result = MemoryMarshal.Cast<byte, float>(remaining.Slice(1, 8))[0];
-                        remaining = remaining.Slice(9);
+                        remaining = remaining.Slice(1);
+                        Span<double> dst = stackalloc double[1];
+                        var dstBytes = MemoryMarshal.AsBytes(dst);
+
+                        // Swap endian
+                        dstBytes[0] = remaining[7];
+                        dstBytes[1] = remaining[6];
+                        dstBytes[2] = remaining[5];
+                        dstBytes[3] = remaining[4];
+                        dstBytes[4] = remaining[3];
+                        dstBytes[5] = remaining[2];
+                        dstBytes[6] = remaining[1];
+                        dstBytes[7] = remaining[0];
+
+                        result = dst[0];
+                        remaining = remaining.Slice(8);
                         return true;
                     }
                 default:
diff --git a/src/Voltaic.Serialization.Etf/Writers/EtfWriter.Float.cs b/src/Voltaic.Serialization.Etf/Writers/EtfWriter.Float.cs
index da383f1..e120bd4 100644
--- a/src/Voltaic.Serialization.Etf/Writers/EtfWriter.Float.cs
+++ b/src/Voltaic.Serialization.Etf/Writers/EtfWriter.Float.cs
@@ -9,11 +9,24 @@ public static partial class EtfWriter
     {
         public static bool TryWrite(ref ResizableMemory<byte> writer, float value, StandardFormat standardFormat)
         {
+            // TODO: Untested, does Discord have any endpoints that accept floats?
             if (standardFormat.IsDefault)
             {
-                Span<float> arr = stackalloc float[] { value };
                 writer.Push((byte)EtfTokenType.NewFloat);
-                MemoryMarshal.AsBytes(arr).CopyTo(writer.GetSpan(8));
+
+                // Swap endian
+                Span<double> src = stackalloc double[] { value };
+                var srcBytes = MemoryMarshal.AsBytes(src);
+                var dst = writer.GetSpan(8);
+                
+                dst[0] = srcBytes[7];
+                dst[1] = srcBytes[6];
+                dst[2] = srcBytes[5];
+                dst[3] = srcBytes[4];
+                dst[4] = srcBytes[3];
+                dst[5] = srcBytes[2];
+                dst[6] = srcBytes[1];
+                dst[7] = srcBytes[0];
                 writer.Advance(8);
             }
             else
@@ -34,11 +47,24 @@ public static bool TryWrite(ref ResizableMemory<byte> writer, float value, Stand
 
         public static bool TryWrite(ref ResizableMemory<byte> writer, double value, StandardFormat standardFormat)
         {
+            // TODO: Untested, does Discord have any endpoints that accept floats?
             if (standardFormat.IsDefault)
             {
-                Span<float> arr = stackalloc float[] { (float)value };
                 writer.Push((byte)EtfTokenType.NewFloat);
-                MemoryMarshal.AsBytes(arr).CopyTo(writer.GetSpan(8));
+
+                // Swap endian
+                Span<double> src = stackalloc double[] { value };
+                var srcBytes = MemoryMarshal.AsBytes(src);
+                var dst = writer.GetSpan(8);
+
+                dst[0] = srcBytes[7];
+                dst[1] = srcBytes[6];
+                dst[2] = srcBytes[5];
+                dst[3] = srcBytes[4];
+                dst[4] = srcBytes[3];
+                dst[5] = srcBytes[2];
+                dst[6] = srcBytes[1];
+                dst[7] = srcBytes[0];
                 writer.Advance(8);
             }
             else
diff --git a/test/Voltaic.Serialization.Etf.Tests/Float.cs b/test/Voltaic.Serialization.Etf.Tests/Float.cs
index 9eca803..a99ee33 100644
--- a/test/Voltaic.Serialization.Etf.Tests/Float.cs
+++ b/test/Voltaic.Serialization.Etf.Tests/Float.cs
@@ -8,7 +8,13 @@ public class SingleTests : BaseTest<float>
     {
         public static IEnumerable<object[]> GetNumberData()
         {
-            throw new NotImplementedException();
+            yield return ReadWrite(EtfTokenType.NewFloat, new byte[] { 0xC7, 0xEF, 0xFF, 0xFF, 0xA0, 0x00, 0x00, 0x00 }, -3.402823e38f); // Min
+            yield return ReadWrite(EtfTokenType.NewFloat, new byte[] { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 }, 0);
+            yield return ReadWrite(EtfTokenType.NewFloat, new byte[] { 0x47, 0xEF, 0xFF, 0xFF, 0xA0, 0x00, 0x00, 0x00 }, 3.402823e38f); // Max
+
+            yield return ReadWrite(EtfTokenType.NewFloat, new byte[] { 0x7F, 0xF0, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 }, float.PositiveInfinity);
+            yield return ReadWrite(EtfTokenType.NewFloat, new byte[] { 0xFF, 0xF0, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 }, float.NegativeInfinity);
+            yield return ReadWrite(EtfTokenType.NewFloat, new byte[] { 0xFF, 0xF8, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 }, float.NaN);
         }
         public static IEnumerable<object[]> GetGData() => TextToBinary(Utf8.Tests.SingleTests.GetGData());
         public static IEnumerable<object[]> GetLittleGData() => TextToBinary(Utf8.Tests.SingleTests.GetLittleGData());
@@ -40,7 +46,13 @@ public class DoubleTests : BaseTest<double>
     {
         public static IEnumerable<object[]> GetNumberData()
         {
-            throw new NotImplementedException();
+            yield return ReadWrite(EtfTokenType.NewFloat, new byte[] { 0xFF, 0xEF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF }, -1.7976931348623157e308d); // Min
+            yield return ReadWrite(EtfTokenType.NewFloat, new byte[] { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 }, 0d);
+            yield return ReadWrite(EtfTokenType.NewFloat, new byte[] { 0x7F, 0xEF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF }, 1.7976931348623157e308d); // Max
+
+            yield return ReadWrite(EtfTokenType.NewFloat, new byte[] { 0x7F, 0xF0, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 }, double.PositiveInfinity);
+            yield return ReadWrite(EtfTokenType.NewFloat, new byte[] { 0xFF, 0xF0, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 }, double.NegativeInfinity);
+            yield return ReadWrite(EtfTokenType.NewFloat, new byte[] { 0xFF, 0xF8, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 }, double.NaN);
         }
         public static IEnumerable<object[]> GetGData() => TextToBinary(Utf8.Tests.DoubleTests.GetGData());
         public static IEnumerable<object[]> GetLittleGData() => TextToBinary(Utf8.Tests.DoubleTests.GetLittleGData());