flask default port code example

Example 1: how to change port in flask app

from flask import Flask
app = Flask(__name__)

@app.route("/")
def hello():
    return "Hello World!"

if __name__ == '__main__':
    app.run(host="localhost", port=8000, debug=True)

Example 2: flask give port number

if __name__ == '__main__':
    app.run(host='0.0.0.0', port=80)

Example 3: how to change port in flask app

if __name__ == "__main__":
    app.run(host='127.0.0.1', port=5002)

Example 4: flask port

from flask import Flask

app = Flask(__name__)

if __name__ == '__main__':
      app.run(port=80)

# Also make sure that nothing else is running on port 80

Example 5: how to change port in flask app

flask run -h localhost -p 3000

Example 6: how to run flask in port 80

sudo apt install authbind
sudo touch /etc/authbind/byport/80
sudo chmod 777 /etc/authbind/byport/80
authbind --deep python3 app.py