Not able to access localhost:5000 with flask

localhost:5000 not working
flask cannot access
localhost 127.0 01 5000
how to access flask app from another computer
flask app run not working
flask app can t be reached
app run localhost flask
flask listen on localhost

This a simple flask program

from flask import Flask

app = Flask(__name__)

@app.route('/')
def index():
    return 'Hello!!'

if __name__ == "__main__":
    app.run(host = '0.0.0.0')

When i run it,

runfile('C:/Users/RB287JD/Documents/Programs/flask_1.py', wdir='C:/Users/RB287JD/Documents/Programs')
 * Running on http://0.0.0.0:5000/ (Press CTRL+C to quit)

But I am unable to access it, I tried http://localhost:5000/ and http://localhost:5000 , both gives me the same error

Not Found The requested URL was not found on the server. If you entered the URL manually please check your spelling and try again.

There are too many same questions here but none of them is clear to me. what is the actual problem here? i could able to access a day before but its not working now


Just call app.run to enable flask to automatically configure:

if __name__ == "__main__":
   app.run()

Can't hit localhost:5000 after following quickstart guide · Issue #54 , and cant seem to open localhost:5000 and this is what I entered CMD flask If you're using Docker Toolbox you'd need to access http://192.168.99.100:5000. Make sure you allow port 22 – not allowing that port means you won’t be able to SSH in, thus you’d either be locked out (if you’re using SSH Keys) or would need to access the console (if you’re using passwords).


Is this code being run externally from your computer? If yes, you need the public IP address of where the flask app is being run from with :5000 on the end. E.g 22.22.222.222:5000 If it is being run on your machine, try changing app.run(host='0.0.0.0') to app.run(host='localhost') and connect to http://localhost:5000 in your browser.

locahost:5000 does not run flask, export FLASK_APP=hello.py $ flask run * Running on http://127.0.0.1:5000/. If you are on It will tell you what it tried to import and why it failed. The most Accessing the URL with a trailing slash produces a 404 “Not Found” error. This helps  @AlexF I cannot justify because I am not a flask developer. But this configuration works for me when I was working on the project. – Muhammad Usman Nov 13 '19 at 11:07


I beleive there is some issue with your loopback address .

Maybe you can try checking ip pf your machine . Use ipconfig on windows and ifconfig on linux command prompt to see ip address of your machine And the use that IP in app.run() E.g

app.run(host = 'your IP')

Then In browser use your IP:port see if this works

Quickstart, We provide an example Flask application for our beloved beers database that database set up; if not, run /opt/dbcourse/examples/db-beers/setup.sh in your VM​. You should then be able to access the Flask app at: http://localhost:5000/ . FLASK_APP=app.py FLASK_ENV=development FLASK_RUN_HOST=[dev-host-ip] FLASK_RUN_PORT=5000 If you have a virtual environment, activate it and do a pip install python-dotenv. This package is going to use the .flaskenv file, and declarations inside it will be automatically imported across terminal sessions. Then you can do flask run


I was running into the same issue but when I got off my company's network and just ran from my home network, it started working. Also I used the following command:

app.run(host = '127.0.0.1')

If you are experiencing this on your own network, you probably have some security setting prohibiting external code to be written to your computer.

Flask Tips – Introduction to Databases (Fall 2018), More About Flask¶. When you executed the flaskhello.py program in the previous section and used a web browser to access it with the url http://localhost:5000/,  for flask specific(if you want to run on specific host and port) app.run(host='0.0.0.0',port='5000', debug=True) It gets started on 0.0.0.0 you can change it to localhost.


14.6. More About Flask, I'm not sure if this is Flask specific, but when I run an app in dev mode (http://​localhost:5000), I cannot access it from other machines on the  Inside the system, running on virtual machine, I can access the running server at 127.0.0.1:5000. Although the 'remote' address of the vm is 192.168.56.101 (ping and ssh work fine), I cannot access the server with 192.168.50.101:5000 neither from the virtual machine nor from the local one. I guess there's something preventing remote connections.


Configure Flask dev server to be visible across the network, Accessing debugger for flask @127.0.0.1:5000 that the server is only accessible from your own computer, not from any other in the network. Not able to access localhost:5000 with flask. Ask Question Asked 2 years, 2 months ago. Active 1 year, 4 months ago. Viewed 4k times 1. 1. This a simple flask program


Accessing debugger for flask @127.0.0.1:5000, I run two commands: docker build -t my-api-docker:latest . docker run -p 5000:  If not, please bind the host to an address other than localhost. Just as the doc said, If you run the server you will notice that the server is only accessible from your own computer, not from any other in the network. This is the default because in debugging mode a user of the application can execute arbitrary Python code on your computer.