Random user agent generator

Each entry is a browser, a platform and a version drawn at random, turned into the exact string that browser sends: Chrome's and Edge's frozen platform tokens and .0.0.0 version, Firefox's rv: and Gecko/20100101. For Chrome and Edge, the Sec-CH-UA brand list is computed with Chromium's own algorithm, the same one on the Chrome user agent page. Every combination this page can produce passes the consistency checks of the user agent checker; the site's tests generate a few hundred and verify each one.

The list is made in your browser and never sent anywhere. Versions: Chrome 157 (Chromium Dash), Edge 157 (Microsoft), Firefox 160 (Mozilla).

Copy the list as JSON and each entry is a ready set of headers: the User-Agent and, for Chrome and Edge, the Client Hints that belong with it. Pass the whole set, not only the user agent, and keep one set for a session:

import json
import random

import requests

# "Copy JSON" above: a list of header sets, each a User-Agent with its Client Hints.
with open("user-agents.json") as f:
    header_sets = json.load(f)

session = requests.Session()
session.headers.update(random.choice(header_sets))  # one identity for the whole session
r = session.get("https://example.com")
print(r.status_code, session.headers["User-Agent"])

For a real browser (Playwright, Puppeteer, Selenium), it is usually better to keep the browser's own user agent: overriding it changes the header and navigator.userAgent, while the Client Hints, workers and engine features keep reporting the real version. See how to change a user agent and what each method changes.

A User-Agent header describes a browser; it does not turn a client into one. Servers compare it with things it cannot touch: the TLS and HTTP/2 handshake, the header order, and, once a page runs JavaScript, the engine's own features and the values in workers. That is why the same string from an HTTP library and from a real Chrome gets different treatment, and why a browser that only rewrites the header keeps its real version everywhere else.