urllib3 vs requests: Which Python HTTP Library Should You Use

HTTP libraries are critical for interacting with the web. They let you send and receive data via HTTP. In Python, making requests is common in tasks like web scraping, API calls, and automation.

If you’re looking to compare urllib3 vs requests to see which library best fits your needs for a project, we’ll cover syntax, readability, performance, features, safety, error-handling, and HTTP support.

What Is urllib3?

urllib3 is a third-party HTTP client library for Python. It’s not included in Python’s standard library, so you must install it separately using pip. It offers robust connection pooling, thread safety, and control over SSL verification.

It’s a lightweight third-party library that gives you detailed handling of HTTP connections.

Main features:

• Connection pooling to reuse TCP connections efficiently.
• Low-level control of request headers, timeouts, and retries.
• Explicit verification settings.

A sample code using urllib3 would look like this:

import urllib3

http = urllib3.PoolManager()
response = http.request(
    "GET",
    "https://example.com",
    headers={"User-Agent": "urllib3-client"}
)
print(response.status, response.data[:100])
response.release_conn()

What is requests?

requests is one of the most popular third-party libraries for making HTTP requests in Python. The requests library has simple, human-readable syntax and powerful features like sessions, auth, file uploads, and JSON handling.

Many tutorials use the requests library for web scraping , APIs, and bots. Here is a sample code made with the requests library:

import requests

response = requests.get(
    "https://example.com",
    headers={"User-Agent": "python-requests"}
)
print(response.status_code, response.text[:100])

Key Differences Between urllib3 and requests

1. Syntax & Readability

• urllib3: More verbose and low-level, which means you manage HTTP connections manually.
• requests: Clean and intuitive, which is ideal for beginners and quick scripts

2. Performance & Features

• urllib3: Great connection pooling, lightweight.
• requests: Built on urllib3, adds lots of features like JSON parsing, sessions, and timeout handling. Retries are also possible, but require extra setup.

3. Thread-Safety & Error Handling

• urllib3: Thread-safe, but you handle exceptions and retries yourself.
• requests: Has built-in session management, easier to send HTTP requests and to handle errors.

4. HTTP Support (GET, POST Handling)

• urllib3 and requests: Both support sending HTTP requests via GET, POST, and more.
• requests: Supports multipart form, file uploads, and making HTTP requests with ease.

When to Use urllib3 vs When to Use requests

urllib3

• For low-level control, high-performance, and advanced pooling of connections.
• Ideal for libraries and background services.
• If you’re building a large-scale service or framework, you may want to use both urllib3 and requests.

requests

• For ease of use, quick scripts, and web scraping , Python requests is best.
• Ideal for beginner-friendly projects and fits most needs.
• If you need session cookies, auth, or quick API calls, go with the requests library.
• For larger projects, you may need to use both urllib3 and requests side-by-side.

How to Install and Use Each Library

Installing and using urllib3 or the requests library is simple. Here’s how to set them up and the differences you’ll see in handling retries, errors, and sending HTTP requests.

Installing urllib3

You can install the standalone version or urllib3 with:

pip install urllib3

Note that Python’s standard library includes urllib.request, but urllib3 is a separate third-party library offering more advanced features.

urllib3 Request Example

import urllib3
from urllib3.exceptions import HTTPError

http = urllib3.PoolManager()

try:
    response = http.request(
        "GET",
        "https://example.com",
        headers={"User-Agent": "custom-client"}
    )
    print(response.status, response.data[:100])  # response data snippet
except HTTPError as e:
    print("Request failed:", e)

Highlights:

• You manually handle connections.
• SSL verification and retries are set up explicitly.
• Lower-level, more control over timeouts and request headers.

Installing requests

To install the requests library, run this:

pip install requests

It’s one of the easiest ways to start making HTTP requests and handling response data quickly.

requests Example With Retry

import requests
from requests.adapters import HTTPAdapter
from urllib3.util.retry import Retry

session = requests.Session()
retry = Retry(
    total=3,
    backoff_factor=0.3,
    status_forcelist=[500, 502, 503, 504]
)
adapter = HTTPAdapter(max_retries=retry)
session.mount("https://", adapter)

try:
    resp = session.get("https://example.com")
    print(resp.status_code, resp.text[:100])
except requests.RequestException as e:
    print("Request failed:", e)

Highlights:

• Built-in session management with retry support.
• Cleaner error handling.
• Great for fast web scraping tasks using clean syntax.

Conclusion

Choosing between urllib3 vs requests comes down to the level of control you need and how complex your project is. Both libraries are excellent at sending requests, but they serve different types of users and use cases.

Before making a decision, think about your project’s scale. If you’re dealing with large-scale web scraping, parallel tasks, or long-running jobs, explore both urllib3 and requests. But for smaller projects, small-scale web scraping, or beginner-level learning, Python requests offers a smoother experience.

If you found this article interesting, you may also want to read about how requests compares against HTTPX and AIOHTTP to see which library works best for web scraping or other projects.