Web Scraping With cURL Made Easy

In 2025, the command line still remains an indispensable tool for developers, especially when it comes to web scraping with cURL. Web scraping with cURL is easy and powerful. cURL is a free tool for the command line. It helps me “talk” to web servers to get data quite easily. It can do many things, like logging in for a user, searching websites that change, all that while using proxy servers. It works with all major protocols, like HTTP and HTTPS. I’ll show you how to use cURL, from simple steps to more complex ones.

What is cURL in Web Scraping?

cURL, which stands for “Client URL,” is a tool used to move data between web servers. It works through different protocols like HTTP, HTTPS, and FTP.cURL. It helps me talk to web servers using commands. With cURL, I can send and get data from websites using different protocols, like HTTP and HTTPS. Whether it’s getting data from APIs or managing files remotely, cURL is reliable and straightforward. It’s one of my favorite tools because it can handle various tasks smoothly.

The cool thing about cURL is its simple commands. I like how easy it is to use and how it can be utilized for many different use cases. People like it because it’s not complicated and can be changed to do what we need. It’s a trusty tool in my data extraction toolkit that helps me with all sorts of tasks involving data on the web.

Prerequisites

Before you start web scraping with cURL, make sure you have it installed on your computer. Here’s how to do it based on your operating system:

A) For Linux: Open the terminal and type the command:

apt-get install curl

B) For Mac: It’s likely already installed, but if you want the latest version, use homebrew:

brew install curl

C) For Windows: If you’re using Windows 10 or newer, cURL should already be there. But for older versions, visit the official website, download the latest release, and install it on your computer.

Once cURL is installed, test it by opening your terminal and typing ‘curl.’ If it’s set up correctly, you’ll see a message like:

curl: try 'curl - help' or 'curl - manual' for more information

That’s it! You’re ready to start scraping the web with cURL.

How to Use cURL for Web Scraping

To send requests with cURL, type ‘curl’ and your target URL in the terminal. That’s all you need to get started!

Terminal

curl https://httpbin.org/anything

You’ll immediately see the HTML content of the webpage on your screen.

To make more advanced requests, you can add extra parameters before the URL:

{
"args": {},
"data": "",
"files": {},
"form": {},
"headers": {
"Accept": "*/*",
"Host": "httpbin.org",
"User-Agent": "curl/7.86.0",
"X-Amzn-Trace-Id": "Root=1–6409f056–52aa4d931d31997450c48daf"
},
"json": null,
"method": "GET",
"origin": "83.XX.YY.ZZ",
"url": "https://httpbin.org/anything"
}

cURL lets you do more by adding extra options before your target URL. You can use protocols like HTTP, HTTPS, and FTP for data transfer. Simply type ‘curl’ and then put options and the website address.

curl [options] [URL]

If you want to submit a form, you’ll need to use the POST method, indicated by the ‘-d’ attribute. For example, if you want to input a username ‘David’ with the password ‘abcd’, you would type:

curl -d "user=David&pass=abcd" https://httpbin.org/post

And here we go:

{
"args": {},
"data":
11 11
"
"files": {}, "form": {
"pass": "abcd",
"user": "David"
},
"headers": {
"Accept": "*/*".
},
"Content-Length": "20",
"Content-Type":
"application/x-www-form-urlencoded",
"Host": "httpbin.org",
"User-Agent": "curl/7.86.0",
"X-Amzn-Trace-Id": "Root-1–6409f198–2ddef75220b12fb80be07a3b"
},

Web Scraping Without Getting Blocked

Avoiding getting blocked while web scraping with cURL can be tricky. To help with that, you’ll learn two methods: using rotating proxies and customizing headers.

Rotating Proxies

Sending lots of requests to a website from the same IP address quickly can make you look like a bot, which might get you blocked. A proxy server can help with this. It acts as a middleman, hiding your real IP address by giving you a different one.

For example, you can find proxy lists online for free and choose an IP address to use in your next request. Please be careful though, free proxies are risky in most cases. Here’s how to do it with cURL:

curl - proxy <proxy-ip>:<proxy-port> <url>

Replace <proxy-ip> with the IP address of the proxy and <proxy-port> with the port number. For instance:

curl - proxy 198.199.86.11:8080 -k https://httpbin.org/anything

Unfortunately, sometimes using free proxies can lead to errors. We might encounter issues like “Received HTTP code 500 from proxy after CONNECT.” To tackle this, you can store a list of proxies in a text file and use a Bash script to test each one automatically. This way, you can rotate through different proxies to avoid being blocked.

curl - proxy 8.209.198.247:80 https://httpbin.org/anything\

You can save a bunch of proxy addresses in a text file. Then, you can make a Bash script to test each proxy automatically. Here’s how it works: The script goes through each line in the proxies.txt file. For each line, it sets that line as the proxy for a cURL request.

#!/bin/bash
# Read the list of proxies from a text file
while read -r proxy; do
echo "Testing proxy: $proxy"
# Make a request through the proxy using cURL
if curl - proxy "$proxy" -k https://httpbin.org/anything
>/dev/null 2>&1; then
curl - proxy "$proxy" -k https://httpbin.org/anything
echo "Success! Proxy $proxy works."
else
echo "Failed to connect to $proxy"
fi
# Wait a bit before testing the next proxy
sleep 1
done < proxies.txt

If the request works and we can access the website through the proxy, the script will show the website content and stop. But if it doesn’t work, we’ll just try the next proxy in the list until we find one that works.

Free proxy pools can be unreliable. A better option is getting a premium proxy with residential IPs. Or, find a more simple solution that handles proxy management for you.

Add Custom Headers

When you browse the web, HTTP headers act like a digital signature, identifying you on every page. So, even if you hide your IP, websites can still tell you’re a bot unless you change your headers.

The most important header for web scraping is the User-Agent string. It tells websites what browser and device you’re using. Here’s an example:

Mozilla/5.0 (Macintosh; Intel Mac OS X 13_2_1) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/16.3 Safari/605.1.15

To change the User-Agent of your cURL scraper, use the ‘-A’ option followed by your desired string. For example:

curl -A "Mozilla/5.0 (X11; Linux x86_64; rv:60.0) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/109.0.0.0 Safari/537.36" https://httpbin.org/headers

Note: Randomly changing the User-Agent might block you because not all the data matches. To avoid this, you can find a list of popular user agents for web scraping with cURL.

Conclusion

cURL is super handy for collecting information from websites, whether the tasks are simple or a bit more complicated. However, I’ve noticed that some websites are making it harder to scrape data using just cURL. That’s why I started pairing it with another tool, helping me get around those tougher defenses. This way, I can keep getting the data I need, even when the websites try to stop me. It’s all about finding new ways to stay ahead and collecting valuable information!