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    isbot πŸ€–/πŸ‘¨β€πŸ¦°

    Detect bots/crawlers/spiders using the user agent string.


    import isbot from 'isbot'
    // Nodejs HTTP
    // ExpressJS
    // Browser
    // User Agent string
    isbot('Mozilla/5.0 (iPhone; CPU iPhone OS 6_0 like Mac OS X) AppleWebKit/536.26 (KHTML, like Gecko) Version/6.0 Mobile/10A5376e Safari/8536.25 (compatible; Googlebot/2.1; +http://www.google.com/bot.html)') // true
    isbot('Mozilla/5.0 (Windows NT 6.1) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/41.0.2228.0 Safari/537.36') // false

    Additional functionality

    Extend: Add user agent patterns

    Add rules to user agent match RegExp: Array of strings

    isbot('Mozilla/5.0') // false
    isbot('Mozilla/5.0') // true

    Exclude: Remove matches of known crawlers

    Remove rules to user agent match RegExp (see existing rules in src/list.json file)

    isbot('Chrome-Lighthouse') // true
    isbot.exclude(['chrome-lighthouse']) // pattern is case insensitive
    isbot('Chrome-Lighthouse') // false

    Find: Verbose result

    Return the respective match for bot user agent rule

    isbot.find('Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Firefox/52.0 DejaClick/') // 'DejaClick'

    Matches: Get patterns

    Return all patterns that match the user agent string

    isbot.matches('Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Firefox/52.0 SearchRobot/1.0') // ['bot', 'search']


    Remove all matching patterns so this user agent string will pass

    const ua = 'Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Firefox/52.0 SearchRobot/1.0';
    isbot(ua) // true
    isbot(ua) // false

    Spawn: Create new instances

    Create new instances of isbot. Instance is spawned using spawner's list as base

    const one = isbot.spawn()
    const two = isbot.spawn()
    one('Chrome-Lighthouse') // true
    two('Chrome-Lighthouse') // false

    Create isbot using custom list (instead of the maintained list)

    const lean = isbot.spawn([ 'bot' ])
    lean('Googlebot') // true
    lean('Chrome-Lighthouse') // false


    • Bot. Autonomous program imitating or replacing some aspect of a human behaviour, performing repetitive tasks much faster than human users could.
    • Good bot. Automated programs who visit websites in order to collect useful information. Web crawlers, site scrapers, stress testers, preview builders and other programs are welcomed on most websites because they serve purposes of mutual benefits.
    • Bad bot. Programs which are designed to perform malicious actions, ultimately hurting businesses. Testing credential databases, DDoS attacks, spam bots.


    What does "isbot" do?

    This package aims to identify "Good bots". Those who voluntarily identify themselves by setting a unique, preferably descriptive, user agent, usually by setting a dedicated request header.

    What doesn't "isbot" do?

    It does not try to recognise malicious bots or programs disguising themselves as real users.

    Why would I want to identify good bots?

    Recognising good bots such as web crawlers is useful for multiple purposes. Although it is not recommended to serve different content to web crawlers like Googlebot, you can still elect to

    • Flag pageviews to consider with business analysis.
    • Prefer to serve cached content and relieve service load.
    • Omit third party solutions' code (tags, pixels) and reduce costs.

    It is not recommended to whitelist requests for any reason based on user agent header only. Instead other methods of identification can be added such as reverse dns lookup.

    Data sources

    We use external data sources on top of our own lists to keep up to date

    Crawlers user agents:

    Non bot user agents:

    Missing something? Please open an issue

    Major releases breaking changes (full changelog)

    Version 3

    Remove testing for node 6 and 8

    Version 2

    Change return value for isbot: true instead of matched string

    Version 1

    No functional change

    Real world data

    Execution times in milliseconds


    npm i isbot



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