diff --git a/NUnitTestComparePDF/NUnitTestComparePDF.csproj b/NUnitTestComparePDF/NUnitTestComparePDF.csproj
index 9008ae3..77e3926 100644
--- a/NUnitTestComparePDF/NUnitTestComparePDF.csproj
+++ b/NUnitTestComparePDF/NUnitTestComparePDF.csproj
@@ -7,7 +7,7 @@
   </PropertyGroup>
 
   <ItemGroup>
-    <PackageReference Include="nunit" Version="3.12.0" />
+    <PackageReference Include="nunit" Version="3.13.1" />
     <PackageReference Include="NUnit3TestAdapter" Version="3.16.1">
       <PrivateAssets>all</PrivateAssets>
       <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>