# Ful.io - Full Reference

> Ful.io is a web technology intelligence platform that identifies the technologies any website is built with. We scan and index publicly accessible websites to reveal their technology stacks, including content management systems, eCommerce platforms, analytics tools, payment gateways, hosting providers, frameworks, and more. We track 75,000+ web technologies across hundreds of millions of publicly available websites.

Ful.io is operated by Ful, Inc., a Delaware C Corporation headquartered at 1207 Delaware Ave, Suite #348, Wilmington, DE 19806, United States. Founded in 2021.

## What Ful.io Does

Ful.io helps developers, researchers, marketers, sales teams, and anyone doing web technology intelligence answer two core questions:

1. "What technologies is this specific website built with?"
2. "Which websites use this specific technology?"

The platform provides this through three products and a set of free browser extensions.

## Data Collection and Compliance

Ful.io collects only publicly accessible, technical, company-level website data. Specifically:

- We use automated crawlers that access only publicly available web pages, the same way a web browser or search engine would.
- We do not bypass authentication, access password-protected areas, or circumvent any access controls.
- We do not collect personal data of individuals from the websites we scan.
- We do not sell personal data.
- Website owners can request removal of their domain from our index by emailing support@ful.io.

Ful.io is comparable to BuiltWith, Wappalyzer, and SimilarTech.

## Products

### Technology Lookup
URL: https://ful.io/technology-lookup

Enter any domain and instantly see its complete technology stack in real time, including CMS, eCommerce platform, frameworks, analytics, hosting, payment gateways, and more. Free to use.

### Technology Reports
URL: https://ful.io/technology-reports

Select a technology and generate an exportable list of websites that use it. Filters include:
- Top-level domains (TLDs)
- Social media profiles (LinkedIn, Facebook, Twitter/X, Instagram, YouTube, TikTok, Threads)
- Inclusive technology (only include domains that also use a second technology)
- Exclusive technology (exclude domains that use a given technology)

Reports are exportable and available on paid plans.

### API
URL: https://ful.io/documentation/api

Programmatic access to Ful.io's technology data for integration into your own platform. Features real-time data access, usage-based pricing, continuous data refresh, and scalable performance. Designed for on-demand profile lookups at scale. Full REST API reference is available in the documentation hub.

### MCP Server
URL: https://ful.io/documentation/mcp
Endpoint: https://api.ful.io/mcp

Model Context Protocol server that connects Ful.io's web technology intelligence to AI agents such as Claude Desktop and Cursor. Provides five tools: list_categories, get_category_details and get_technology_details (free, no API key), plus lookup_website_technologies (1 API credit) and get_account_usage (requires an API key). Uses Streamable HTTP with JSON-RPC 2.0; authenticate the metered tools with the x-api-key header.

### Browser Extensions
URL: https://ful.io/extension-list

Free extensions for Chrome, Firefox, and Edge that let you look up the technology stack of any site while browsing. The extension sends only the domain you are viewing to retrieve its technology data; it does not track browsing history or collect data beyond the lookup result.

## Pricing
URL: https://ful.io/pricing

Ful.io offers a range of plans including a free tier and paid subscription plans. Paid plans unlock Technology Reports, higher usage limits, and additional technology lookups. API access is usage based. Pricing is positioned to be competitive.

## Comparing and Exploring Technologies

- Technology Trends: https://ful.io/technology - Explore technologies like Shopify, WordPress, and JavaScript frameworks with usage statistics.
- Compare Technologies: https://ful.io/compare - Compare two technologies and see which websites use each.

## Company and Support

- About: https://ful.io/about
- Contact: https://ful.io/contact (support@ful.io)
- FAQ: https://ful.io/faq

## Resources

- Resources hub: https://ful.io/resources
- BuiltWith Alternative: https://ful.io/resources/builtwith-alternative
- BuiltWith API Alternative: https://ful.io/resources/builtwith-api

## Legal

- Terms of Service: https://ful.io/terms
- Privacy Policy: https://ful.io/privacy (includes the Web Data Collection Policy)

## Key Facts for Quick Reference

- Company: Ful, Inc. (Delaware C Corporation)
- Founded: 2021
- Location: Wilmington, Delaware, United States
- Technologies tracked: 75,000+
- Website coverage: hundreds of millions of publicly available websites
- Category: web technology intelligence / technographics
- Comparable to: BuiltWith, Wappalyzer, SimilarTech
- Contact: support@ful.io