JS to check if a Shopify site is headless

check-headless-shopify.min.js

!function(){let e=0;if(window?.__remixContext?.state?.loaderData?.root?.analytics?.shopifySalesChannel==="hydrogen"){alert("Is Headless (Hydrogen)");return}!window.Shopify&&e++,document.querySelectorAll('link[href^="https://cdn.shopify.com/oxygen"]').length>0&&e++,window.__remixContext&&e++,document.querySelectorAll('script[src*="_nuxt"]').length>0&&e++,document.querySelectorAll('script[src*="_next"]').length>0&&e++,document.getElementById("___gatsby")&&e++,e>1?alert("Probably Headless"):e>0?alert("Maybe Headless"):alert("Probably Not Headless")}();

check-headless-shopify.unmin.js

(function() {
    // JS code to check if a site is headless or not
    let score = 0;

    if(window?.__remixContext?.state?.loaderData?.root?.analytics?.shopifySalesChannel === 'hydrogen') {
        // Definitely Hydrogen just alert and return
        alert('Is Headless (Hydrogen)');
        return;
    }

    // Online storefront sites use window.Shopify
    if(!window.Shopify) {
        score++;
    }

    // Sites with resources that start with https://cdn.shopify.com/oxygen are usually headless
    if(document.querySelectorAll('link[href^="https://cdn.shopify.com/oxygen"]').length > 0) {
        score++;
    }

    // Sites built on remix are usually headless
    if(window.__remixContext) {
        score++;
    }

    // Sites built with nuxt are usually headless
    if(document.querySelectorAll('script[src*="_nuxt"]').length > 0) {
        score++;
    }

    // Sites built with next are usually headless
    if(document.querySelectorAll('script[src*="_next"]').length > 0) {
        score++;
    }

    // Sites built with gatsby are usually headless
    if(document.getElementById('___gatsby')) {
        score++;
    }

    if(score > 1) {
        alert('Probably Headless');
    } else if(score > 0) {
        alert('Maybe Headless');
    } else {
        alert('Probably Not Headless');
    }
})();