Flask Cookies Last Updated : 24 Mar, 2025 Comments Improve Suggest changes Like Article Like Report Cookies store user data in the browser as key-value pairs, allowing websites to remember logins, preferences, and other details. This helps improve the user experience by making the site more convenient and personalized.Make sure that flask is already installed on our system - Flask InstallationSetting Cookies in Flaskset_cookie( ) method: Using this method we can generate cookies in any application code. The syntax for this cookies setting method:Response.set_cookie(key, value = '', max_age = None, expires = None, path = '/', domain = None, secure = None, httponly = False)Parameters: key – Name of the cookie to be set.value – Value of the cookie to be set.max_age – should be a few seconds, None (default) if the cookie should last as long as the client’s browser session.expires – should be a datetime object or UNIX timestamp.domain – To set a cross-domain cookie.path – limits the cookie to given path, (default) it will span the whole domain.Example: Python from flask import Flask, request, make_response app = Flask(__name__) # Using set_cookie( ) method to set the key-value pairs below. @app.route('/setcookie') def setcookie(): # Initializing response object resp = make_response('Setting the cookie') resp.set_cookie('GFG','ComputerScience Portal') return resp app.run() Running the code in Visual Studio Code application.My Visual Studio Code terminalOutput: Go to the above-mentioned url in the terminal -For Example - http://127.0.0.1:5000/route-name. Here the route-name is setcookie.OutputGetting Cookies in Flaskcookies.get( )This get( ) method retrieves the cookie value stored from the user's web browser through the request object. Python from flask import Flask, request, make_response app = Flask(__name__) # getting cookie from the previous set_cookie code @app.route('/getcookie') def getcookie(): GFG = request.cookies.get('GFG') return 'GFG is a '+ GFG app.run() Output:getcookieLogin Application in Flask using cookiesLet's create a simple login page in Flask using cookies.First, create the main Python file, app.py.Then, design the login page Login.html, where users can enter their username and password.In app.py, store the username as a cookie to track the logged-in user.Retrieve the stored cookie from the browser and display it on the user details page.app.py Python from flask import Flask, request, make_response, render_template app = Flask(__name__) @app.route('/', methods = ['GET']) def Login(): return render_template('Login.html') @app.route('/details', methods = ['GET','POST']) def login(): if request.method == 'POST': name = request.form['username'] output = 'Hi, Welcome '+name+ '' resp = make_response(output) resp.set_cookie('username', name) return resp app.run(debug=True) Login.html HTML <!DOCTYPE html> <html> <head> <title>Login</title> </head> <body> <form method="post" action="/details"> <label for="username">Username</label> <input type="text" name="username" id="username"/> <br/> <br> <label for="password">Password</label> <input type="password" name="password" id="password"/> <br/> <br> <input type="submit" name="submit" id="submit" value="Login"/> </form> </body> </html> Output:Login PageUser LoggingUser Logged In and Cookie TrackerFrom the image above, we can see the website's cookies. The 'username' is the key, and its value 'Greeshma' shows that cookies store data as key-value pairs.To view cookies in your browser:Click the three-dot menu in the top-right corner.Go to More Tools > Developer Tools.Open the Application tab. Tracking Website Visitors Using CookiesWe will track the number of visitors to our website using cookies. Since we haven't previously stored a "visitors count" variable, the cookie will default to 0 (as per Python's dictionary behavior).For a first-time visitor, the count starts at 0.With each visit, the count increases.The make_response() function is used to generate a response object and set the updated visitor count in the cookie. Python from flask import Flask, request, make_response app = Flask(__name__) app.config['DEBUG'] = True @app.route('/') def vistors_count(): # Converting str to int count = int(request.cookies.get('visitors count', 0)) # Getting the key-visitors count value as 0 count = count+1 output = 'You visited this page for '+str(count) + ' times' resp = make_response(output) resp.set_cookie('visitors count', str(count)) return resp @app.route('/get') def get_vistors_count(): count = request.cookies.get('visitors count') return count app.run() Output: Url - http://127.0.0.1:5000OutputUrl for below output- http://127.0.0.1:5000/getVisitors count output using cookiesIn the above output screenshot, the value of the website visitors count is retrieved using request.cookies.get( ) method.Cookies Tracking in Browser Cookie Tracker for visitors count applicationThe flask cookies can be secured by putting the secure parameter in response.set_cookie('key', 'value', secure = True) and it is the best-recommended practice to secure cookies on the internet. Comment More infoAdvertise with us Next Article How to return a JSON response from a Flask API ? G greeshmanalla Follow Improve Article Tags : Technical Scripter Python Technical Scripter 2022 Python Flask Practice Tags : python Similar Reads Flask Tutorial Flask is a lightweight and powerful web framework for Python. It’s often called a "micro-framework" because it provides the essentials for web development without unnecessary complexity. Unlike Django, which comes with built-in features like authentication and an admin panel, Flask keeps things mini 8 min read Flask Setup & InstallationIntroduction to Web development using FlaskFlask is a lightweight and flexible web framework for Python. It's designed to make getting started with web development quick and easy, while still being powerful enough to build complex web applications. It is an API of Python that allows us to build web applications. 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