var ua = navigator.userAgent;

if (/Firefox\//.test(ua))
   var Firefox = /Firefox\/([0-9\.A-z]+)/.exec(ua)[1];

这让我有了火狐的版本，

    let versionNumber = parseInt(window.navigator.userAgent.match(/Firefox\/([0- 
    9]+)\./)[1]);

使用这个:http://www.quirksmode.org/js/detect.html

alert(BrowserDetect.browser); // will say "Firefox"
alert(BrowserDetect.version); // will say "3" or "4"

我根据Hermann Ingjaldsson的回答写了一个版本检测器，但是更健壮，它返回一个包含名称/版本数据的对象。它涵盖了主要的浏览器，但我不介意过多的移动浏览器和小浏览器:

function getBrowserData(nav) {
    var data = {};

    var ua = data.uaString = nav.userAgent;
    var browserMatch = ua.match(/(opera|chrome|safari|firefox|msie|trident(?=\/))\/?\s*([\d\.]+)/i) || [];
    if (browserMatch[1]) { browserMatch[1] = browserMatch[1].toLowerCase(); }
    var operaMatch = browserMatch[1] === 'chrome';
    if (operaMatch) { operaMatch = ua.match(/\bOPR\/([\d\.]+)/); }

    if (/trident/i.test(browserMatch[1])) {
        var msieMatch = /\brv[ :]+([\d\.]+)/g.exec(ua) || [];
        data.name = 'msie';
        data.version = msieMatch[1];
    }
    else if (operaMatch) {
        data.name = 'opera';
        data.version = operaMatch[1];
    }
    else if (browserMatch[1] === 'safari') {
        var safariVersionMatch = ua.match(/version\/([\d\.]+)/i);
        data.name = 'safari';
        data.version = safariVersionMatch[1];
    }
    else {
        data.name = browserMatch[1];
        data.version = browserMatch[2];
    }

    var versionParts = [];
    if (data.version) {
        var versionPartsMatch = data.version.match(/(\d+)/g) || [];
        for (var i=0; i < versionPartsMatch.length; i++) {
            versionParts.push(versionPartsMatch[i]);
        }
        if (versionParts.length > 0) { data.majorVersion = versionParts[0]; }
    }
    data.name = data.name || '(unknown browser name)';
    data.version = {
        full: data.version || '(unknown full browser version)',
        parts: versionParts,
        major: versionParts.length > 0 ? versionParts[0] : '(unknown major browser version)'
    };

    return data;
};

它可以这样使用:

var brData = getBrowserData(window.navigator || navigator);
console.log('name: ' + brData.name);
console.log('major version: ' + brData.version.major);
// etc.

navigator.sayswho= (function(){ var ua= navigator.userAgent, tem, M= ua.match(/(opera|chrome|safari|firefox|msie|trident(?=\/))\/?\s*(\d+)/i) || []; if(/trident/i.test(M[1])){ tem= /\brv[ :]+(\d+)/g.exec(ua) || []; return 'IE '+(tem[1] || ''); } if(M[1]=== 'Chrome'){ tem= ua.match(/\b(OPR|Edge)\/(\d+)/); if(tem!= null) return tem.slice(1).join(' ').replace('OPR', 'Opera'); } M= M[2]? [M[1], M[2]]: [navigator.appName, navigator.appVersion, '-?']; if((tem= ua.match(/version\/(\d+)/i))!= null) M.splice(1, 1, tem[1]); return M.join(' '); })(); console.log(navigator.sayswho); // outputs: `Chrome 62`

为此，您需要检查navigator的值。appVersion或navigator.userAgent 尝试使用:

console.log(navigator.appVersion)