WhatWeb - Next generation web scanner

Developed by Andrew Horton urbanadventurer and Brendan Coles bcoles

Latest Release: v0.6.3. October 18, 2025

License: GPLv2

This product is subject to the terms detailed in the license agreement. For more information about WhatWeb visit https://github.com/urbanadventurer/

Wiki: https://github.com/urbanadventurer/WhatWeb/wiki/

If you have any questions, comments or concerns regarding WhatWeb, please consult the documentation prior to contacting one of the developers. Your feedback is always welcome.

Contents

• About WhatWeb
• Example Usage
• Usage
• Logging & Output
• Plugins
• Aggression
• Performance & Stability
• Optional Dependencies
• Writing Plugins
• Updates & Additional Information
• Release History
• Credits

About WhatWeb

WhatWeb identifies websites. Its goal is to answer the question, "What is that Website?". WhatWeb recognises web technologies including content management systems (CMS), blogging platforms, statistic/analytics packages, JavaScript libraries, web servers, and embedded devices. WhatWeb has over 1800 plugins, each to recognise something different. WhatWeb also identifies version numbers, email addresses, account IDs, web framework modules, SQL errors, and more.

WhatWeb can be stealthy and fast, or thorough but slow. WhatWeb supports an aggression level to control the trade off between speed and reliability. When you visit a website in your browser, the transaction includes many hints of what web technologies are powering that website. Sometimes a single webpage visit contains enough information to identify a website but when it does not, WhatWeb can interrogate the website further. The default level of aggression, called 'stealthy', is the fastest and requires only one HTTP request of a website. This is suitable for scanning public websites. More aggressive modes were developed for use in penetration tests.

Most WhatWeb plugins are thorough and recognise a range of cues from subtle to obvious. For example, most WordPress websites can be identified by the meta HTML tag, e.g. '<meta name="generator" content="WordPress 2.6.5">', but a minority of WordPress websites remove this identifying tag but this does not thwart WhatWeb. The WordPress WhatWeb plugin has over 15 tests, which include checking the favicon, default installation files, login pages, and checking for "/wp-content/" within relative links.

Features

• Over 1800 plugins
• Control the trade off between speed/stealth and reliability
• Performance tuning. Control how many websites to scan concurrently with automatic output optimization.
• Multiple log formats: Brief (greppable), Verbose (human readable), XML, JSON, MagicTree, RubyObject, MongoDB, ElasticSearch, SQL.
• Proxy support including TOR
• Custom HTTP headers
• Basic HTTP authentication
• Control over webpage redirection
• IP address ranges
• Fuzzy matching
• Result certainty awareness
• Custom plugins defined on the command line
• IDN (International Domain Name) support
• Dual-protocol scanning for simple hostnames (automatically tests both HTTP and HTTPS)

Example Usage

Using WhatWeb to scan reddit.com.

$ ./whatweb reddit.com
http://reddit.com [301 Moved Permanently] Country[UNITED STATES][US], HTTPServer[snooserv], IP[151.101.65.140], RedirectLocation[https://www.reddit.com/], UncommonHeaders[retry-after,x-served-by,x-cache-hits,x-timer], Via-Proxy[1.1 varnish]
https://www.reddit.com/ [200 OK] Cookies[edgebucket,eu_cookie_v2,loid,rabt,rseor3,session_tracker,token], Country[UNITED STATES][US], Email[banner@2x.png,snoo-home@2x.png], Frame, HTML5, HTTPServer[snooserv], HttpOnly[token], IP[151.101.37.140], Open-Graph-Protocol[website], Script[text/javascript], Strict-Transport-Security[max-age=15552000; includeSubDomains; preload], Title[reddit: the front page of the internet], UncommonHeaders[fastly-restarts,x-served-by,x-cache-hits,x-timer], Via-Proxy[1.1 varnish], X-Frame-Options[SAMEORIGIN]

Usage

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$$$$     $$. .$$$  $$$ .$$$$$$.  .$$$$$$$$$$. $$$$     $$. .$$$$$$$. .$$$$$$. 
$ $$     $$$ $ $$  $$$ $ $$$$$$. $$$$$ $$$$$$ $ $$     $$$ $ $$   $$ $ $$$$$$.
$ `$     $$$ $ `$  $$$ $ `$  $$$ $$' $ `$ `$$ $ `$     $$$ $ `$      $ `$  $$$'
$. $     $$$ $. $$$$$$ $. $$$$$$ `$  $. $  :' $. $     $$$ $. $$$$   $. $$$$$.
$::$  .  $$$ $::$  $$$ $::$  $$$     $::$     $::$  .  $$$ $::$      $::$  $$$$
$;;$ $$$ $$$ $;;$  $$$ $;;$  $$$     $;;$     $;;$ $$$ $$$ $;;$      $;;$  $$$$
$$$$$$ $$$$$ $$$$  $$$ $$$$  $$$     $$$$     $$$$$$ $$$$$ $$$$$$$$$ $$$$$$$$$'

WhatWeb - Next generation web scanner version 0.6.3.
Developed by Andrew Horton (urbanadventurer) and Brendan Coles (bcoles)
Homepage: https://morningstarsecurity.com/research/whatweb

Usage: whatweb [options] <URLs>

TARGET SELECTION:
  <TARGETs>             Enter URLs, hostnames, IP addresses, filenames or
                        IP ranges in CIDR, x.x.x-x, or x.x.x.x-x.x.x.x
                        format.
  --input-file=FILE, -i Read targets from a file. You can pipe
                        hostnames or URLs directly with -i /dev/stdin.

TARGET MODIFICATION:
  --url-prefix          Add a prefix to target URLs.
  --url-suffix          Add a suffix to target URLs.
  --url-pattern         Insert the targets into a URL. Requires --input-file,
                        eg. www.example.com/%insert%/robots.txt 

AGGRESSION:
  The aggression level controls the trade-off between speed/stealth and
  reliability.
  --aggression, -a=LEVEL Set the aggression level. Default: 1.
  Aggression levels are:
  1. Stealthy   Makes one HTTP request per target. Also follows redirects.
  3. Aggressive If a level 1 plugin is matched, additional requests will be
      made.
  4. Heavy      Makes a lot of HTTP requests per target. Aggressive tests from
      all plugins are used for all URLs.

HTTP OPTIONS:
  --user-agent, -U=AGENT Identify as AGENT instead of WhatWeb/0.6.3.
  --header, -H          Add an HTTP header. eg "Foo:Bar". Specifying a default
                        header will replace it. Specifying an empty value, eg.
                        "User-Agent:" will remove the header.
  --follow-redirect=WHEN Control when to follow redirects. WHEN may be `never',
                        `http-only', `meta-only', `same-site', or `always'.
                        Default: always.
  --max-redirects=NUM   Maximum number of contiguous redirects. Default: 10.

AUTHENTICATION:
  --user, -u=<user:password> HTTP basic authentication.
  --cookie, -c=COOKIES  Provide cookies, e.g. 'name=value; name2=value2'.
  --cookiejar=FILE      Read cookies from a file.
  --no-cookies          Disable automatic cookie handling (improves performance 
                        with high thread counts).

### Cookie Handling

WhatWeb automatically handles cookies across redirects by default. This improves fingerprinting accuracy on sites requiring session management.

- `--cookie, -c=COOKIES`  - Set initial cookies manually
- `--cookie-jar=FILE`  - Load cookies from file  
- `--no-cookies`  - Disable automatic cookie handling

**Performance Note:** With high thread counts (>100), cookie handling may impact performance. Use `--no-cookies` for maximum speed on large scans.

PROXY:
  --proxy           <hostname[:port]> Set proxy hostname and port.
                    Default: 8080.
  --proxy-user      <username:password> Set proxy user and password.

PLUGINS:
  --list-plugins, -l            List all plugins.
  --info-plugins, -I=[SEARCH]   List all plugins with detailed information.
                                Optionally search with keywords in a comma
                                delimited list.
  --search-plugins=STRING       Search plugins for a keyword.
  --plugins, -p=LIST  Select plugins. LIST is a comma delimited set of 
                      selected plugins. Default is all.
                      Each element can be a directory, file or plugin name and
                      can optionally have a modifier, eg. + or -
                      Examples: +/tmp/moo.rb,+/tmp/foo.rb
                      title,md5,+./plugins-disabled/
                      ./plugins-disabled,-md5
                      -p + is a shortcut for -p +plugins-disabled.

  --grep, -g=STRING|REGEXP      Search for STRING or a Regular Expression. Shows 
                                only the results that match.
                                Examples: --grep "hello"
                                --grep "/he[l]*o/"
  --custom-plugin=DEFINITION  Define a custom plugin named Custom-Plugin,
                        Examples: ":text=>'powered by abc'"
                        ":version=>/powered[ ]?by ab[0-9]/"
                        ":ghdb=>'intitle:abc \"powered by abc\"'"
                        ":md5=>'8666257030b94d3bdb46e05945f60b42'"
  --dorks=PLUGIN        List Google dorks for the selected plugin.

OUTPUT:
  --verbose, -v         Verbose output includes plugin descriptions. Use twice
                        for debugging.
  --colour,--color=WHEN control whether colour is used. WHEN may be `never',
                        `always', or `auto'.
  --quiet, -q           Do not display brief logging to STDOUT.
  --no-errors           Suppress error messages.

LOGGING:
  --log-brief=FILE        Log brief, one-line output.
  --log-verbose=FILE      Log verbose output.