diff --git a/tests/Tokenizer.Tests/Tokenizer.Tests.csproj b/tests/Tokenizer.Tests/Tokenizer.Tests.csproj
index 45792408..7bc76768 100644
--- a/tests/Tokenizer.Tests/Tokenizer.Tests.csproj
+++ b/tests/Tokenizer.Tests/Tokenizer.Tests.csproj
@@ -15,7 +15,7 @@
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     <PackageReference Include="Microsoft.Extensions.Configuration.Json" Version="10.0.10" />
-    <PackageReference Include="NSubstitute" Version="5.3.0" />
+    <PackageReference Include="NSubstitute" Version="6.0.0" />
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     <PackageReference Include="Serilog.Extensions.Logging" Version="8.0.0" />
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