Use the navigator userAgent property to detect User Agent in JavaScript. You have to match the browser name to identify the user browser.
User Agent JavaScript detection
A simple example code calls this JS function on page load, and this will display the user browser name on page load.
<!DOCTYPE html>
<html lang="en">
<body>
<script>
function fnBrowserDetect(){
let userAgent = navigator.userAgent;
let browserName;
if(userAgent.match(/chrome|chromium|crios/i)){
browserName = "chrome";
}else if(userAgent.match(/firefox|fxios/i)){
browserName = "firefox";
} else if(userAgent.match(/safari/i)){
browserName = "safari";
}else if(userAgent.match(/opr\//i)){
browserName = "opera";
} else if(userAgent.match(/edg/i)){
browserName = "edge";
}else{
browserName="No browser detection";
}
console.log("You are using ", browserName);
}
fnBrowserDetect()
</script>
</body>
</html>
Output:
We use navigator.userAgent with indexof to figure out the browser name.
var browserName = (function (agent) {
switch (true) {
case agent.indexOf("edge") > -1: return "MS Edge";
case agent.indexOf("edg/") > -1: return "Edge ( chromium based)";
case agent.indexOf("opr") > -1 && !!window.opr: return "Opera";
case agent.indexOf("chrome") > -1 && !!window.chrome: return "Chrome";
case agent.indexOf("trident") > -1: return "MS IE";
case agent.indexOf("firefox") > -1: return "Mozilla Firefox";
case agent.indexOf("safari") > -1: return "Safari";
default: return "other";
}
})(window.navigator.userAgent.toLowerCase());
document.querySelector("h1").innerText="You are using "+ browserName +" browser";
- Accessing the User Agent String:
navigator.userAgent
retrieves the user agent string, which contains information about the browser, version, and operating system.
- Displaying the User Agent String:
- The user agent string is displayed in a paragraph element with the id
userAgent
.
- The user agent string is displayed in a paragraph element with the id
- Detecting the Browser:
- A simple check using
indexOf
to see if the user agent string contains certain substrings like"Chrome"
,"Firefox"
,"Safari"
,"MSIE"
, or"Trident"
. - Depending on the presence of these substrings, a message is logged to the console indicating the detected browser.
- A simple check using
Do comment if you have any doubts or suggestions on this JS code.
Note: The All JS Examples codes are tested on the Firefox browser and the Chrome browser.
OS: Windows 10
Code: HTML 5 Version