Matches either hubspot domain or hs-sites (sandboxes)

hs-regex.js

// url => https://regex101.com/r/jhw0wy/1

const regex = /https:\/\/([a-z\.]{4})?([0-9]+.hs-sites|hubspot).com[\/]?/gm;

// Alternative syntax using RegExp constructor
// const regex = new RegExp('https:\/\/([a-z\.]{4})?([0-9]+.hs-sites|hubspot).com[\/]?', 'gm')

const str = `https://hubspot.com/
https://123456.hs-sites.com/
https://google.com`;
let m;

while ((m = regex.exec(str)) !== null) {
    // This is necessary to avoid infinite loops with zero-width matches
    if (m.index === regex.lastIndex) {
        regex.lastIndex++;
    }
    
    // The result can be accessed through the `m`-variable.
    m.forEach((match, groupIndex) => {
        console.log(`Found match, group ${groupIndex}: ${match}`);
    });
}