diff --git a/CHANGELOG.md b/CHANGELOG.md
index 20304be..46e9563 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -6,6 +6,10 @@ Versioning](https://semver.org/spec/v2.0.0.html).
 
 ## [Unreleased]
 
+### Breaking Changes
+
+- **Docker default port changed from 8080 to 80**: The `ENV DevOidcToolkit__Port=8080` environment variable has been removed from the Dockerfile. The application now listens on port 80 by default (the application's built-in default). Docker port mappings should be updated from `-p 8080:8080` to `-p 8080:80`. This fixes a bug where setting `Port` in `config.json` had no effect (see [#26](https://github.com/BusinessSimulations/dev-oidc-toolkit/issues/26))
+
 ## [0.6.0]
 - Add optional SQLite persistence via `Database.SqliteFile` config option; defaults to in-memory when not set (see [#20](https://github.com/BusinessSimulations/dev-oidc-toolkit/issues/20))
 
diff --git a/DevOidcToolkit.Documentation/docs/configuration.md b/DevOidcToolkit.Documentation/docs/configuration.md
index cb06473..43e0723 100644
--- a/DevOidcToolkit.Documentation/docs/configuration.md
+++ b/DevOidcToolkit.Documentation/docs/configuration.md
@@ -14,7 +14,7 @@ Dev OIDC Toolkit can be configured using environment variables. The environment
 Here is how to run the application in a Docker container with environment variables:
 
 ```bash
-docker run -p 8080:8080                                                               \
+docker run -p 8080:80                                                                \
     -e DevOidcToolkit__Users__0__Email=test@localhost                                 \
     -e DevOidcToolkit__Users__0__FirstName=Test                                       \
     -e DevOidcToolkit__Users__0__LastName=User                                        \
@@ -166,7 +166,7 @@ When running the application in a Docker container, the `config.json` file shoul
 Here is how to run the application in a Docker container with a configuration file mounted:
 
 ```bash
-docker run -p 8080:8080 -v ./config.json:/app/config.json ghcr.io/businesssimulations/dev-oidc-toolkit
+docker run -p 8080:80 -v ./config.json:/app/config.json ghcr.io/businesssimulations/dev-oidc-toolkit
 ```
 
 ### Reference
@@ -485,7 +485,7 @@ In-memory database (default, no persistence):
 ```json
 {
     "DevOidcToolkit": {
-        "Port": 8080,
+        "Port": 80,
         "Issuer": "https://fake-issuer.example.com",
         "Users": [
             {
@@ -512,7 +512,7 @@ SQLite database (data persists across restarts):
 ```json
 {
     "DevOidcToolkit": {
-        "Port": 8080,
+        "Port": 80,
         "Database": {
             "SqliteFile": "/data/dev-oidc-toolkit.db"
         },
diff --git a/Dockerfile b/Dockerfile
index 29854bd..be9cc05 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -36,11 +36,11 @@ COPY --from=build /app/dist .
 
 RUN apt-get update && apt-get install -y --no-install-recommends curl && rm -rf /var/lib/apt/lists/*
 
+ENV DevOidcToolkit__Address=0.0.0.0
+
 ENTRYPOINT ["dotnet", "dev-oidc-toolkit.dll"]
 
-ENV DevOidcToolkit__Port=8080
-ENV DevOidcToolkit__Address=0.0.0.0
-EXPOSE 8080
+EXPOSE 80
 
 HEALTHCHECK --interval=30s --timeout=3s --start-period=5s --retries=3 \
-    CMD curl -f http://localhost:${DevOidcToolkit__Port}/healthz/live || exit 1
+    CMD curl -f http://localhost:80/healthz/live || exit 1
diff --git a/README.md b/README.md
index 0326ff0..7105f10 100644
--- a/README.md
+++ b/README.md
@@ -52,7 +52,7 @@ Access the documentatation here: <https://dev-oidc-toolkit.readthedocs.io/en/lat
 The easiest way to run this application is using docker, use this command:
 
 ```bash
-docker run -p 8080:8080                                                               \
+docker run -p 8080:80                                                                \
     -e DevOidcToolkit__Users__0__Email=test@localhost                                 \
     -e DevOidcToolkit__Users__0__FirstName=Test                                       \
     -e DevOidcToolkit__Users__0__LastName=User                                        \