Find every company using any web technology
Look up the tech stack behind any website, then build a targeted list of every company that uses it, filtered to your market and ready to export.
One platform
Everything you need to turn tech signals into pipeline
Look up any site for free, then build and export targeted reports of the companies that match.
Technology Lookup
Enter any website and instantly see its full stack: CMS, frameworks, analytics, hosting, payments and more. Free to try.
Look up a site →Technology Reports
Build a report of every company using a technology. Filter by country, domain ending and social presence, then export or send to your CRM.
Build a report →Compare Technologies
Put two technologies side by side: market reach, regional footprint, and where each one actually wins. Great for positioning.
Compare two techs →How it works
Build a targeted technology report in three steps
Pick a technology
Start from any of 75,000+ technologies, like every store running Shopify or Klaviyo.
Filter to your market
Narrow by country, domain ending (.com, .co.uk…) and the social profiles they link to.
Export or sync
Download a clean CSV or push the report straight into your CRM, ready to prospect.
Live dataset
Explore the largest live web technology intelligence dataset
Every technology, ranked by how many sites use it and refreshed as we crawl the web. Explore the technology signals behind hundreds of millions of sites, by technology or category.
Who it's for
One dataset, many plays
Sales & prospecting
Find every company using a competitor or complementary tool and build a targeted report.
Marketers
Size a market by technology and target campaigns to the exact stack you integrate with.
Developers
Check what any site is built with and track adoption trends across frameworks over time.
Recruiters
Source companies by the exact technologies your candidates specialise in.
Take it everywhere
In your browser, or in your code
Browser extensions
Identify any website's tech stack in one click, right from the page you're on. Free for Chrome, Firefox and Edge.
Chrome
Firefox
EdgeAPI & integrations
Pull the same data programmatically, connect it to an AI agent over MCP, or enrich your CRM records automatically.
GET https://api.ful.io/domain-search?url=stripe.com
→ { "technologies": [ … 58 detected … ] }
Testimonials
Here's what our customers say about us
“Ful.io has been a game-changer for our market research. The ability to instantly analyze what technologies our competitors are using has helped us make informed decisions about our own tech stack. Highly recommended for any growing startup.”
FAQ
Questions, answered
What is Ful.io?
How does Ful.io work?
Is Ful.io free to use?
Does Ful.io offer API access?
Every company on a technology, in one report
Pick a technology, filter to your market, and export a clean list of the companies that use it.