Browser developer tools expose what a page loads, how it is structured, and what happens in the browser. Use these techniques only on applications you own or are authorized to test.
⚡ Quick Reference
| Tab / Technique | Best For |
|---|---|
| Console | Running JavaScript and inspecting browser-side behavior |
| Inspector / Elements | Reviewing HTML, forms, attributes, and page structure |
| Network | Observing requests, responses, scripts, and other loaded resources |
robots.txt |
Discovering paths a site asks search engines not to crawl |
💻 Console
Modify a Cookie
Run JavaScript in the console to set a browser cookie:
document.cookie = 'cookieID=true'
document.cookie = 'cookieID=false'
A cookie changed in the browser does not automatically grant server-side authorization. Secure applications validate permissions on the server.
🧭 URL Discovery Idea
Check whether the site publishes a robots.txt file:
https://website.test/robots.txt
This file can reveal paths that site owners have asked search engines not to index.
🧱 Inspector
Use the Inspector or Elements tab to review the page’s HTML source. It can help identify:
- How forms and input fields are structured
- Form actions, methods, names, and hidden values
- Whether JavaScript controls page behavior
- Element IDs, classes, attributes, and embedded metadata
🌐 Network
The Network tab shows the resources and requests made while a page loads or while you interact with it. It can reveal:
- JavaScript files the page relies on
- Request methods, headers, parameters, and payloads
- HTTP response codes and timing
- API requests and their responses
Reload the page with the Network tab already open to capture the complete initial request sequence.