Why Every SEO Should Learn Curl (And How to Start in 5 Minutes)
Most SEOs rely on Screaming Frog, Sitebulb, or Chrome DevTools to check how a website is performing technically. All brilliant tools, but there’s something faster, free, and already installed on your computer: a tiny program called curl.
First, what’s a “terminal”?
Before computers had pretty desktops and clickable icons, you controlled them by typing instructions. That text-based interface is called a terminal, or on Windows, Command Prompt. Think of it as texting your computer directly: you type a command, it does the thing, and prints text back at you.
It’s still around today because for certain technical jobs, typing one line is faster than clicking through ten menus.
What is curl?
curl stands for “Client URL.” It’s a built-in tool on Windows, Mac, and Linux that fetches webpages without rendering them. Instead of seeing the pretty version your browser shows you, you see the raw response the server sends back. Exactly what Googlebot sees when it crawls your site.
That’s the gold for SEO. Your browser hides things; curl shows everything.
Your first curl check in 4 steps
- Open Command Prompt. Press the Windows key, type
cmd, hit Enter. - Type the command:
curl -I https://yourdomain.com(the capital I means “headers only”). - Hit Enter. The server’s response headers print out instantly.
- Read the results. Status code is on line one — 200 means OK, 301 means redirect, 404 means missing.
That’s it. You’ve just made the same request Google makes to your site thousands of times a day.
Why this matters for SEO
A single curl check reveals things a browser hides: status codes (is the page actually returning 200?), caching rules (is the CDN configured properly?), security headers (HSTS, X-Frame-Options), server fingerprints (what platform is the site built on?), and redirect chains (are there unnecessary hops slowing down crawling?).
It’s also the fastest way to spot staging environments accidentally leaking into Google’s index, broken canonicals, or compression that’s silently switched off.
Save the full response for deeper analysis
Want the entire HTML page too? Use this:
curl -i --compressed https://yourdomain.com > response.txt
That saves the complete response, headers and HTML- to a text file you can open in VS Code or Notepad++. Brilliant for auditing canonicals, hreflang, structured data, and meta tags in seconds.
The takeaway
Curl is the closest thing you’ll get to seeing your site through Google’s eyes. Five minutes to learn, a lifetime of faster audits. Open Command Prompt today and try it on your homepage, you’ll be amazed what it tells you.
It’s a way of pulling info from websites, without a browser. I think
Small Business Dad 