A/B Testing & Personalization
1,843 of the 1,000,000 top sites in our Tranco top-1M census run Optimizely (0.2%). An experimentation platform for running A/B tests and personalizing website content. Detection is homepage-level HTML/header fingerprinting, so a site can run Optimizely on other pages without it showing here.
Other a/b testing & personalization
| # | Domain | Global traffic rank | Contacts |
|---|---|---|---|
| 1 | bit.ly | #102 (Tranco) | Find emails |
| 2 | bbc.com | #210 (Tranco) | Find emails |
| 3 | hp.com | #270 (Tranco) | Find emails |
| 4 | salesforce.com |
| Site | Tranco rank | Also detected | Contacts |
|---|---|---|---|
| circleci.com | #10,628 | 6sense, Algolia, Amazon (ACM) + 34 more | Find emails |
| winzip.com | #10,644 | Amazon CloudFront, Amazon Route 53, Apache + 14 more | Find emails |
| authorize.net | #10,744 | Akamai Edge DNS, ClickTale (Contentsquare), Cloudflare + 11 more | Find emails |
| #274 (Tranco) |
| Find emails |
| 5 | gitlab.com | #393 (Tranco) | Find emails |
| gofund.me | #10,814 | Amazon (ACM), Amazon CloudFront, Amazon Route 53 + 8 more | Find emails |
| pingdom.net | #10,990 | Adobe Experience Cloud (Launch), Cloudflare, DigiCert + 13 more | Find emails |
| edweek.org | #11,050 | Adobe Experience Cloud (Launch), Amazon (ACM), Amazon CloudFront + 6 more | Find emails |
| dealer.com | #11,272 | Adobe Fonts (Typekit), Let's Encrypt, Nginx + 7 more | Find emails |
| mulesoft.com | #11,305 | Adobe Audience Manager, Akamai edge/CDN, Akamai mPulse + 11 more | Find emails |
| computerweekly.com | #11,508 | Chartbeat, Cloudflare edge/CDN, DoubleClick (Google Ads) + 6 more | Find emails |
| petfinder.com | #11,516 | Akamai Bot Manager, Akamai edge/CDN, Amazon CloudFront + 9 more | Find emails |
| chick-fil-a.com | #11,618 | Cloudflare Bot Management, Cloudflare edge/CDN, Google Tag Manager + 7 more | Find emails |
| plarium.com | #11,709 | Cloudflare, Cloudflare Bot Management, Cloudflare edge/CDN + 6 more | Find emails |
| sigmaaldrich.com | #11,753 | Akamai Bot Manager, Akamai edge/CDN, DigiCert + 6 more | Find emails |
| synthesia.io | #11,888 | AWS Lambda, Amazon Route 53, Cloudflare edge/CDN + 4 more | Find emails |
| lendingtree.com | #11,930 | Amazon Route 53, Cloudflare Bot Management, Cloudflare edge/CDN + 4 more | Find emails |
| publix.com | #12,144 | Adobe Experience Cloud (Launch), Akamai Bot Manager, Akamai Edge DNS + 7 more | Find emails |
| freshrelease.com | #12,161 | Amazon CloudFront, Amazon Route 53, Cloudflare Bot Management + 8 more | Find emails |
| earnin.com | #12,226 | Amazon Route 53, Contentful, Google Tag Manager + 7 more | Find emails |
| aspca.org | #12,235 | Cloudflare edge/CDN, DoubleClick (Google Ads), Drupal + 9 more | Find emails |
| unisys.com | #12,288 | Amazon Route 53, Azure API Management, Cloudflare edge/CDN + 6 more | Find emails |
| birkenstock.com | #12,313 | Akamai Bot Manager, Akamai edge/CDN, Cloudflare edge/CDN + 8 more | Find emails |
| checkout.com | #12,395 | AWS Lambda, Checkout.com, Cloudflare edge/CDN + 8 more | Find emails |
| altium.com | #12,486 | AddToAny, Amazon (ACM), Amazon CloudFront + 34 more | Find emails |
| nowtv.com | #12,529 | Adobe Experience Cloud (Launch), Akamai Edge DNS, DigiCert + 4 more | Find emails |
| uts.edu.au | #12,540 | Akamai Edge DNS, Azure API Management, Cloudflare edge/CDN + 7 more | Find emails |
From the Crawlora Website Tech Stack Dataset, a homepage-level fingerprint of a 1,000,000-domain Tranco top-1M census (run top1m-2026-08-25-full-v2), snapshot August 29, 2026. Directional, not exhaustive — fully custom or bundled stacks under-detect. Methodology →