diff --git a/Decimal2D.Tests/Decimal2D.Tests.csproj b/Decimal2D.Tests/Decimal2D.Tests.csproj
index d74995a..6e1ebe3 100644
--- a/Decimal2D.Tests/Decimal2D.Tests.csproj
+++ b/Decimal2D.Tests/Decimal2D.Tests.csproj
@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
-    <TargetFramework>netcoreapp2.2</TargetFramework>
+    <TargetFramework>net9.0</TargetFramework>
     <Configurations>Debug;Release;DebugWithMessages</Configurations>
     <Platforms>AnyCPU</Platforms>
   </PropertyGroup>
@@ -12,9 +12,11 @@
   </PropertyGroup>
 
   <ItemGroup>
-    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="16.2.0" />
-    <PackageReference Include="NUnit" Version="3.12.0" />
-    <PackageReference Include="NUnit3TestAdapter" Version="3.13.0" />
+    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.12.0" />
+    <PackageReference Include="Newtonsoft.Json" Version="13.0.3" />
+    <PackageReference Include="NUnit" Version="4.3.0" />
+    <PackageReference Include="NUnit3TestAdapter" Version="5.0.0-beta.5" />
+    <PackageReference Include="System.Text.RegularExpressions" Version="4.3.1" />
   </ItemGroup>
 
   <ItemGroup>
diff --git a/Decimal2D.Tests/Point2DTests.cs b/Decimal2D.Tests/Point2DTests.cs
index b2b042c..3c9ea7d 100644
--- a/Decimal2D.Tests/Point2DTests.cs
+++ b/Decimal2D.Tests/Point2DTests.cs
@@ -10,8 +10,8 @@ public class Point2DTests
         public void TestConstructor(int x, int y)
         {
             var p = new Point2D(x, y);
-            Assert.AreEqual(p.X, x);
-            Assert.AreEqual(p.Y, y);
+            Assert.That(p.X, Is.EqualTo(x));
+            Assert.That(p.Y, Is.EqualTo(y));
         }
 
         [TestCase(0, 3, true)]
@@ -37,7 +37,7 @@ public void TestQuadrant(int x, int y, int quadrant)
         public void TestQuadrantOnAxis(int x, int y)
         {
             var p = new Point2D(x, y);
-            Assert.Throws<Exception>(() => {var q = p.Quadrant;});
+            Assert.Throws<Exception>(() => { var q = p.Quadrant; });
         }
 
         [TestCase("0", "3", "0", "3", "0")]
@@ -47,7 +47,7 @@ public void TestDistanceTo(string x1, string y1, string x2, string y2, string di
         {
             var p1 = new Point2D(Convert.ToDecimal(x1), Convert.ToDecimal(y1));
             var p2 = new Point2D(Convert.ToDecimal(x2), Convert.ToDecimal(y2));
-            Assert.AreEqual(p1.DistanceTo(p2), Convert.ToDecimal(distance));
+            Assert.That(p1.DistanceTo(p2), Is.EqualTo(Convert.ToDecimal(distance)));
         }
     }
 }
diff --git a/Decimal2D/Decimal2D.csproj b/Decimal2D/Decimal2D.csproj
index ac24dc1..58b49b6 100644
--- a/Decimal2D/Decimal2D.csproj
+++ b/Decimal2D/Decimal2D.csproj
@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
-    <TargetFramework>netstandard2.0</TargetFramework>
+    <TargetFramework>net9.0</TargetFramework>
     <Description>Portable math support for Decimal-based geometric and trigonometric calculations.</Description>
     <Authors>Nathan P Jones</Authors>
     <PackageId>DecimalMath.Decimal2D</PackageId>
diff --git a/DecimalEx.Tests/DecimalEx.Tests.csproj b/DecimalEx.Tests/DecimalEx.Tests.csproj
index 8222590..6d21bdd 100644
--- a/DecimalEx.Tests/DecimalEx.Tests.csproj
+++ b/DecimalEx.Tests/DecimalEx.Tests.csproj
@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
-    <TargetFramework>netcoreapp2.2</TargetFramework>
+    <TargetFramework>net9.0</TargetFramework>
     <Configurations>Debug;Release;DebugWithMessages</Configurations>
     <Platforms>AnyCPU</Platforms>
   </PropertyGroup>
@@ -12,9 +12,11 @@
   </PropertyGroup>
 
   <ItemGroup>
-    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="16.2.0" />
-    <PackageReference Include="NUnit" Version="3.12.0" />
-    <PackageReference Include="NUnit3TestAdapter" Version="3.13.0" />
+    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.12.0" />
+    <PackageReference Include="Newtonsoft.Json" Version="13.0.3" />
+    <PackageReference Include="NUnit" Version="4.3.0" />
+    <PackageReference Include="NUnit3TestAdapter" Version="5.0.0-beta.5" />
+    <PackageReference Include="System.Text.RegularExpressions" Version="4.3.1" />
   </ItemGroup>
 
   <ItemGroup>
diff --git a/DecimalEx.Tests/DecimalExTests/SqrtTests.cs b/DecimalEx.Tests/DecimalExTests/SqrtTests.cs
index 70c2697..d10bec4 100644
--- a/DecimalEx.Tests/DecimalExTests/SqrtTests.cs
+++ b/DecimalEx.Tests/DecimalExTests/SqrtTests.cs
@@ -58,7 +58,7 @@ public void TestRange()
                                           Debug.WriteLine("Sqrt({0})={1}", i, DecimalEx.Sqrt(i));
                                           reset.Set();
                                       });
-                Assert.IsTrue(reset.WaitOne(30000));
+                Assert.That(reset.WaitOne(30000),Is.True);
 
                 step *= 1.01m;
                 try { i += step; }
diff --git a/DecimalEx/DecimalEx.csproj b/DecimalEx/DecimalEx.csproj
index 693bfa5..d6b1d5f 100644
--- a/DecimalEx/DecimalEx.csproj
+++ b/DecimalEx/DecimalEx.csproj
@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
-    <TargetFramework>netstandard2.0</TargetFramework>
+    <TargetFramework>net9.0</TargetFramework>
     <Description>Portable math support for Decimal that Microsoft forgot and more.
 
 Includes Decimal versions of Sqrt, Pow, Exp, and Log as well as the trig functions Sin, Cos, Tan, ASin, ACos, ATan, ATan2.