Wappalyzer - Wappalyzer is a technology profilers and leads data provider. Create lists of websites and contacts that use certain technologies.
Clearbit - Clearbit provides Business Intelligence APIs
BuiltWith - Find out the technology behind websites
Lusha - Search less. Sell more.
WhatRuns - Extension that helps you identify technologies used on any website at the click of a button.
Datanyze - The sales prospecting tool powered by technology data