
WhatRuns
Discover what runs a website
About WhatRuns
WhatRuns is a free browser extension that identifies the technologies powering any website with a single click. It detects CMS platforms, frameworks, analytics tools, CDNs, WordPress plugins, themes, fonts and more, and can notify you when a site you follow adds or removes a technology.
Pros & Cons
Pros
- Completely free with no account or sign-up required
- Detects WordPress plugins, themes and fonts that many rivals miss
- Fast one-click workflow with a clean, simple interface
- Lightweight extension with negligible browser slowdown
- Follow-and-notify feature tracks when sites change their stack
- Frequently updated technology database
Cons
- No native mobile app and the web experience is weak on phones
- Backend and server-side technology detection is less reliable
- Cannot show historical tech changes for sites you weren't already following
- Few native integrations compared to enterprise tools like BuiltWith
- Depth of company/lead data trails dedicated sales-intelligence platforms
Key Features
One-click tech detection
Click the extension icon on any website to instantly see the full stack of technologies it uses.
Broad technology coverage
Identifies CMSs, frameworks, web apps, analytics, advertising tools, CDNs and hosting providers.
WordPress plugins and themes
Uncovers the specific WordPress plugins, themes and fonts a site is running, which many competitors miss.
Follow websites
Follow any site and get notified when it starts or stops using a particular technology.
Constantly updated database
New web apps and technologies are added regularly so detection stays current with the latest tools.
No sign-up required
Install the extension and start detecting technologies immediately with no account needed.
Lightweight performance
A small extension that runs in the browser with negligible impact on page load and performance.
Pricing
- One-click technology detection on any website
- Detects CMS, frameworks, analytics, CDNs and more
- WordPress plugins, themes and fonts detection
- Follow websites for technology-change alerts
- No sign-up required
Best For
Competitive intelligence
Quickly profile a competitor's tech stack to understand the tools and platforms they rely on.
Agency client research
Inspect a prospect's website before a pitch to tailor proposals around their existing technologies.
Developer curiosity and learning
Find out which frameworks, libraries and services power sites you admire.
Lead qualification
Identify sites running a specific platform or plugin to target prospects that fit your product.
Monitoring tech adoption
Follow key websites to be alerted when they adopt or drop technologies over time.
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