WhatWeb
WhatWeb identifies the technologies a website uses, such as the web server, CMS, JavaScript libraries and frameworks.
Legal & ethical use. Use this tool only on systems, networks and data that you own or have explicit written permission to test. Unauthorised access or scanning can break computer-misuse laws (for example Pakistan's Prevention of Electronic Crimes Act, 2016, and equivalents elsewhere). Practise in your own lab or in authorised environments such as CTFs.
What it is used for
- Fingerprint your own sites for an asset inventory
- See which versions are exposed to visitors
Key features
- Large plugin set
- Aggression levels
- Multiple output formats
Installation
Install from your distribution (`sudo apt install whatweb`) or clone the repository (Ruby).
Beginner usage guide
Run with the default aggression level first; higher levels send more requests and are noisier.
Example commands
Run these only against your own lab or authorised targets. Placeholder addresses such as 192.0.2.x are documentation ranges.
Fingerprint a lab web server
whatweb http://127.0.0.1:8081Prints detected technologies and versions for the target.
References
Source verification
Last reviewed: 2026-10-27
Links checked over HTTP: 2026-10-27 07:51 UTC — official: 200, docs: 200, repo: 200
Command flags checked against the real binary whatweb (WhatWeb version 0.6.4 ( https://morningstarsecurity.com/rese...) on 2026-10-27.