Tech Stack Guides
149 articles
How to Tell if a Website Uses an A/B Testing Tool
Optimizely, VWO, AB Tasty and Convert leave fingerprints: anti-flicker snippets, _vwo cookies and window globals. Here is how to detect a site's test tool.
How to Tell if a Website Is Built with Laravel
Laravel hides on the server, but it leaks tells: XSRF-TOKEN and laravel_session cookies, /storage/ paths and Blade markers. Here is how to spot each one.
How to Tell if a Website Is Built with BigCommerce
BigCommerce leaves clear fingerprints: cdn11.bigcommerce.com assets, /stencil/ theme paths and a window.BCData object. Here is how to detect it in under a minute.
How to Tell if a Website Is Built with Astro
Astro leaves clear fingerprints: astro-island elements, an Astro generator meta tag and _astro/ asset paths. Here is how to detect it in under a minute.
How to Tell if a Website Uses HubSpot
HubSpot leaves clear fingerprints: js.hs-scripts.com tracking code, hubspotutk and __hstc cookies, and hsforms embeds. Here is how to detect it quickly.
How to Check if a Website Uses Google Tag Manager
Google Tag Manager leaves clear signals: a gtm.js script, a GTM-XXXXXX container ID, the dataLayer array and a noscript iframe. Here is how to detect it.
How to Tell if a Website Is Built with Wix or Squarespace
Wix and Squarespace leave distinct fingerprints. Here is how to tell them apart using headers, asset domains, generator tags and cookies, side by side.
How to Tell if a Website Is Built with Webflow
Webflow leaves clear fingerprints. Here is how to confirm a site is built with Webflow using the data-wf-page attribute, the generator tag and webflow.js.
How to Read a Website's HTTP Response Headers
HTTP response headers reveal a site's server, CDN, caching, cookies and security posture. Here is what each header means and how to read them yourself.
How to Identify a WordPress Theme and Its Plugins
Once you know a site runs WordPress, here is how to find its theme and its plugins — from the source, the style.css header and asset paths to detectors.
How to Detect Live Chat and Chatbot Tools on a Website
Intercom, Drift, Zendesk, Tidio, Crisp — chat widgets load from recognisable domains. Here is how to detect a site's live-chat and chatbot tools from DevTools.
How to Find What Email Marketing Platform a Website Uses
Mailchimp, Klaviyo, HubSpot, ConvertKit — email platforms leave form actions and scripts behind. Here is how to detect a site's ESP from its signup form.
How to Find Out What Programming Language a Website Is Built In
Identify the server-side language behind any site — PHP, Node.js, Python, Ruby, ASP.NET or Java — from HTTP headers, cookies, URL extensions and errors.
How to Check What JavaScript Libraries a Website Uses
Detect the JavaScript libraries behind any site — jQuery, React, Vue, lodash, GSAP and more — using the DevTools console, the Network tab and detectors.
How to Find Out What Payment Processor a Website Uses
Stripe, PayPal, Adyen, Square — payment processors leave scripts and network calls behind. Here is how to detect a site's payment gateway from the checkout.
How to Tell What CMS a Website Is Using
A practical guide to identifying the content management system behind any site — WordPress, Drupal, Joomla or headless — from source, headers and tools.
How to Tell if a Website Is Built with Next.js
Next.js leaves clear fingerprints: /_next/static/ asset paths, a __NEXT_DATA__ script and React underneath. Here is how to detect it in under a minute.
How to Find Out What Analytics a Website Uses
How to detect the analytics and tracking tools a website runs — Google Analytics, Tag Manager, Meta Pixel and more — from the page source and network requests.
How to Find Out How Old a Website Is (Domain Age & History)
How to check a website's age using WHOIS registration dates and the Wayback Machine — plus what domain age really means for trust and SEO, and where it misleads.
How to Check a Website's Traffic (Free Estimation Methods)
You cannot see another site's real analytics, but you can estimate its traffic. Here are the free tools and signals to gauge how much traffic a website gets — and how reliable they are.
How to Find a Website's IP Address (and What It Reveals)
Several quick ways to find any website's IP address — ping, nslookup, browser devtools and online tools — plus what the IP actually reveals about hosting, location and CDNs.
How to Tell If a Website Uses Cloudflare (or Another CDN)
How to detect whether a site sits behind Cloudflare, Fastly, CloudFront or another CDN — using response headers, DNS and a few quick checks — and why it matters.
What Website Builder Is This? How to Detect Wix, Squarespace, Webflow & More
Website builders leave unmistakable fingerprints. Learn the exact tells for Wix, Squarespace, Webflow, GoDaddy, Weebly, Framer and Carrd — and how to read them in seconds.
How to Find Out What E-commerce Platform a Website Uses
Identify the e-commerce platform behind any online store — Shopify, WooCommerce, Magento, BigCommerce and more — using asset domains, headers and checkout tells.