diff --git a/.github/workflows/dotnet.yml b/.github/workflows/dotnet.yml
index 1dabaf1..ad24a74 100644
--- a/.github/workflows/dotnet.yml
+++ b/.github/workflows/dotnet.yml
@@ -28,7 +28,7 @@ jobs:
 
       - uses: actions/setup-dotnet@v1.8.2
         with:
-          dotnet-version: 2.1.815
+          dotnet-version: 6.0.x
 
       - uses: actions/cache@v2.1.6
         env:
@@ -85,7 +85,7 @@ jobs:
       - name: setup dotnet
         uses: actions/setup-dotnet@v1.8.2
         with:
-          dotnet-version: 3.1
+          dotnet-version: 6.0.x
           source-url: https://nuget.pkg.github.com/linked-data-dotnet/index.json
         env:
           NUGET_AUTH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
@@ -105,7 +105,7 @@ jobs:
 
       - uses: actions/setup-dotnet@v1.8.2
         with:
-          dotnet-version: 2.1.401
+          dotnet-version: 6.0.x
           source-url: https://api.nuget.org/v3/index.json
         env:
           NUGET_AUTH_TOKEN: ${{ secrets.NUGET_API_KEY }}
diff --git a/Dockerfile b/Dockerfile
index 1680d80..5fcb9c6 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -3,8 +3,8 @@
 #> docker build -t json-ld.net .
 #> docker run --rm json-ld.net dotnet test -v normal
 
-# .NET Core 2.1 on Ubuntu 18.04 LTS
-FROM mcr.microsoft.com/dotnet/core/sdk:2.1-bionic
+# .NET Core 6.0 on Ubuntu 20.04 LTS
+FROM mcr.microsoft.com/dotnet/sdk:6.0-focal
 
 WORKDIR /App
 
diff --git a/test/json-ld.net.tests/json-ld.net.tests.csproj b/test/json-ld.net.tests/json-ld.net.tests.csproj
index fd0ea7e..cd1af6c 100644
--- a/test/json-ld.net.tests/json-ld.net.tests.csproj
+++ b/test/json-ld.net.tests/json-ld.net.tests.csproj
@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
-    <TargetFrameworks>netcoreapp2.1</TargetFrameworks>
+    <TargetFramework>net6.0</TargetFramework>
     <GenerateRuntimeConfigurationFiles>true</GenerateRuntimeConfigurationFiles>
     <GenerateAssemblyConfigurationAttribute>false</GenerateAssemblyConfigurationAttribute>
     <GenerateAssemblyCompanyAttribute>false</GenerateAssemblyCompanyAttribute>