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 |
|---|---|---|---|
| newschool.edu | #17,194 | ASP.NET, Cloudflare edge/CDN, CrazyEgg + 3 more | Find emails |
| zattoo.com | #17,219 | Akamai Edge DNS, Cloudflare Bot Management, Cloudflare Turnstile + 11 more | Find emails |
| ucs.org | #17,226 | Cloudflare, Cloudflare edge/CDN, Drupal + 4 more | Find emails |
| #274 (Tranco) |
| Find emails |
| 5 | gitlab.com | #393 (Tranco) | Find emails |
| dsw.com |
| #17,450 |
| Braintree, CSC (Digital Brand Services), Google Trust Services + 4 more |
| Find emails |
| eiu.com | #17,538 | Amazon CloudFront, Cloudflare Bot Management, Cloudflare edge/CDN + 10 more | Find emails |
| skybroadband.com | #17,558 | Akamai Bot Manager, Akamai edge/CDN, Branch + 6 more | Find emails |
| infoblox.com | #17,756 | Adobe Experience Cloud (Launch), Adobe Fonts (Typekit), Fastly + 8 more | Find emails |
| worldofwarcraft.com | #18,023 | Amazon (ACM), Amazon Route 53, Google Tag Manager + 3 more | Find emails |
| travelers.com | #18,048 | Azure API Management, Cloudflare Bot Management, Cloudflare edge/CDN + 6 more | Find emails |
| connectwise.com | #18,068 | ASP.NET, Adobe Fonts, Adobe Fonts (Typekit) + 18 more | Find emails |
| format.com | #18,091 | Cloudflare, Cloudflare Bot Management, Cloudflare edge/CDN + 10 more | Find emails |
| 23andme.com | #18,137 | Amazon CloudFront, Cloudflare, Cloudflare Bot Management + 9 more | Find emails |
| mural.co | #18,171 | AWS Lambda, Amazon Route 53, Cloudflare edge/CDN + 11 more | Find emails |
| cdw.com | #18,234 | ASP.NET, Akamai Bot Manager, Akamai Edge DNS + 7 more | Find emails |
| atieva.com | #18,366 | Amazon (ACM), Amazon CloudFront, Amazon Route 53 + 7 more | Find emails |
| o2.co.uk | #18,401 | Amazon CloudFront, Amazon S3, Azure Front Door + 7 more | Find emails |
| bloggersdelight.dk | #18,502 | Apache, Bootstrap, DigiCert + 11 more | Find emails |
| kiva.org | #18,814 | Adobe Fonts (Typekit), Amazon Route 53, Fastly + 11 more | Find emails |
| navexglobal.com | #18,940 | Google Tag Manager, Let's Encrypt, Microsoft 365 + 4 more | Find emails |
| aib.ie | #19,021 | Adobe Experience Manager Edge Delivery (Helix RUM), Akamai edge/CDN, Akamai mPulse + 6 more | Find emails |
| dolby.com | #19,099 | Amazon Route 53, Azure API Management, Chatbase + 3 more | Find emails |
| bravotv.com | #19,100 | Adobe Analytics, Adobe Experience Cloud (Launch), Akamai Edge DNS + 11 more | Find emails |
| trstp.io | #19,143 | Amazon (ACM), Amazon Route 53, Foundation + 5 more | Find emails |
| brandwatch.com | #19,220 | Bizible, CHEQ, Cloudflare + 10 more | Find emails |
| kidney.org | #19,423 | ConsentMo, Drupal, Fastly + 6 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 →