AgentData vs BuiltWith: free tech stacks, with the people behind them
BuiltWith for long-tail coverage and history; AgentData for the people behind the stack, free.
BuiltWith is the reference database for website technology, with 127,643 trackable technologies and 18 years of history, and its individual site lookups are free. The moment you need the API, lead lists or exports, it costs $295 to $995 a month, unchanged since at least 2013. AgentData detects 4,077 technologies across 133M domains, pairs every stack with the company's email addresses and people, and gives you the API, the MCP server and exports for $0 with no card. Every figure on this page was checked against BuiltWith's own pages on 17 September 2026.
BuiltWith is the product I'd point you at if you needed to know what ran on a website in 2009. Gary Brewer has kept it running, kept it accurate and, remarkably, kept the price flat for thirteen years while everyone else in this market moved to credits. We built AgentData's detection on the same idea and we're honest that we cover a fraction of the technologies they do. What we couldn't accept was that knowing a company runs Intercom should cost $295 a month before you can ask who runs support there. So we made the stack, the people and the emails one free lookup, and we put an MCP server in front of it so your agent can ask instead of you.
The verdict
Choose AgentData if you…- want the company's tech stack and its verified emails and people in one lookup
- are building an AI agent and want an MCP server or REST API without a $295 a month minimum
- need exports, filters by technology and sector, and switch signals, for free
- work outside the US: our profiles come from crawling websites everywhere
- want to test a data layer before ever paying for one
- need niche technology coverage: 127,643 technologies against our 4,077
- need technology history back 18 years, not months
- need country-level market share and trend reports (trends.builtwith.com)
- already have BuiltWith wired into Salesforce, HubSpot or Zoho and it's working
One company, two responses
Both APIs return JSON for a domain. BuiltWith's Domain API returns the stack, detection dates and a Meta block; AgentData's lookup returns the stack plus the company profile, verified emails, people and web signals. Left is the field structure from BuiltWith's Domain API documentation (api.builtwith.com/domain-api, read 17 September 2026); right is AgentData's documented /api/v1/lookup response.
{
"Results": [{
"Result": {
"Paths": [{
"Technologies": [{
"Name": "Twitter Platform",
"Tag": "javascript",
"FirstDetected": "2012-07-29T14:00:00Z",
"LastDetected": "2018-04-30T14:00:00Z",
"IsPremium": "no"
}]
}]
},
"Meta": {
"CompanyName": "Rodale Inc.",
"Vertical": "Technology and Computing",
"Emails": ["support@site.com"],
"Telephones": ["+1-650-745-0728"],
"Names": [],
"Social": ["https://x.com/website"],
"ARank": 0, "QRank": 0
}
}]
}Requires a paid plan and API key; credits tracked via X-API-CREDITS-* headers. The Free API returns technology groups (analytics, CMS, hosting) and counts, not technology names, at 1 request per second.
{
"domain": "stripe.com",
"company": {
"name": "Stripe", "sector": "Financial Services & Fintech",
"vertical": "Payments", "b2b_b2c": "b2b", "size": "large",
"headquarters_country": "US", "email_pattern": "first.last",
"signals": { "has_pricing_page": true, "has_api_docs": true, "has_careers_page": true }
},
"technologies": [
{ "name": "React", "category": "Framework", "confidence": "high" },
{ "name": "Segment", "category": "Analytics", "confidence": "high" }
],
"emails": { "total": 42, "verified": 38,
"data": [{ "email": "jane.smith@stripe.com", "title": "VP Engineering",
"confidence": 95, "verification_status": "valid", "verified_at": "2026-09-01T10:30:00Z" }] },
"people": { "total": 156, "data": [{ "name": "…", "title": "CTO", "seniority": "c_level" }] },
"lookup": { "consumed": true, "remaining": 999 }
}Free account, Bearer key, 1,000 lookups a day at 5 requests a second. company.*, signals, emails and people are fields BuiltWith's response doesn't carry beyond its Meta block.
BuiltWith's Meta block does include emails, telephones and names where it has them, and BuiltWith lead lists include contact names, emails and titles. The difference is depth and verification: AgentData's emails are SMTP-verified with a confidence score and a verified_at date; BuiltWith publishes no verification method.
AgentData vs BuiltWith at a glance
AgentDataPricing and features verified 17 September 2026 against builtwith.com/plans and api.builtwith.com; confirm current details on each vendor's site.
Why agent builders and growth teams pick AgentData over BuiltWith
The question after “what do they run?” is “who do I talk to?” AgentData answers both.
Technologies, sector, size, verified emails and people in one responseBuiltWith's site lookups are free. Its API starts at $295 a month. Ours is $0 at 1,000 lookups a day.
Sign up, generate a key, call /api/v1/lookupcurl -H "Authorization: Bearer $KEY" \
"https://agentdata.run/api/v1/lookup?domain=stripe.com"Connect Claude Code, Claude Desktop or Cursor in one command and ask for companies by technology.
Hosted MCP and npm package, freeclaude mcp add agentdata --transport http https://mcp.agentdata.run/mcp \
--header "Authorization: Bearer YOUR_API_KEY"
# then: "Find UK e-commerce companies running Shopify and Klaviyo, with the head of marketing's verified email."lookup_companysearch_companiesfind_peopleget_technologiesget_signalscheck_usageBuiltWith tells you a technology's trend line. AgentData tells you which company dropped it last month.
/signals lists tool removals and additions per company, with datesOur profiles come from crawling the sites themselves, so a Leeds agency and a Lisbon SaaS are covered the same way.
133M domains indexed, updated dailyPricing: AgentData vs BuiltWith
Both products are free for looking up one site at a time. The comparison that matters is the first paid step: BuiltWith's is $295 a month; AgentData's is Pro at $99 a year.
You keep at least $2,952/yr with AgentData at this volume.
BuiltWith prices from builtwith.com/plans, 17 September 2026: $295 / $495 / $995 a month, or $2,950 / $4,950 / $9,950 a year (annual equivalents shown). Basic and Pro include 1 login; Team includes unlimited logins. Pro ($495) adds unlimited reports for a single login and is omitted from the slider. AgentData: 1,000 lookups a day, 5 requests a second, fair use.
Pricing history 2021–2026
BuiltWith has held $295 / $495 / $995 since at least November 2019, and Basic has been $295 since at least June 2013. In real terms that's a 19% price cut against US inflation, which is to their credit. It's also $3,540 a year for the cheapest API access. Entry paid plan per month. Cells link to the archived pricing page they were read from (Arquivo.pt). *2021 inferred from identical 2019 and 2022 captures. CPI: BLS CUUR0000SA0 annual averages; 2026 = June 2026.
What changed
- BuiltWith: Basic has been $295 since at least June 2013, and no plan price has changed since November 2019. Additions only: Live Feed API, VAT and company-number API, AI Readiness Scores (June 2026), MCP API (February 2026).
- AgentData: $19 / $49 / $99 tiers specced April 2026, never launched; free for everyone since May 2026.
AgentData vs BuiltWith, feature by feature
Coverage: where BuiltWith is bigger, and where it matters
BuiltWith tracks 127,643 technologies; we track 4,077. If you need to know a site runs an obscure WordPress plugin, use BuiltWith.
- AgentData: Our catalogue is weighted to the tools that drive B2B decisions: CRMs, support and chat, analytics, payments, marketing automation, e-commerce, infrastructure.
- BuiltWith: For “companies using Intercom” or “sites on Shopify with Klaviyo”, both answer; for a specific jQuery carousel from 2014, only BuiltWith does.
Source: builtwith.com/plans (127,643 trackable technologies, 491.9M domains), 17 September 2026
Contacts: who's actually verified
Both return emails. Only one tells you whether they'll bounce.
- AgentData: Every email has verification_status, confidence (0–100) and verified_at; role-based addresses are flagged.
- BuiltWith: Emails, telephones and names appear in the Meta block and lead lists; the documentation states no verification method.
Source: api.builtwith.com/domain-api Meta fields; agentdata.run/docs, 17 September 2026
History vs signals
BuiltWith's FirstDetected / LastDetected go back to 2012 in their own example. Our history is months, but we surface the change as a signal you can filter on.
- AgentData: /api/v1/signals returns tool added and removed per company with dates; the /signals page lists them.
- BuiltWith: 18 years of technology trends; company-level changes via the paid Change API.
Source: api.builtwith.com (Change API listed as paid), 17 September 2026
Agent access
Same job, different entry price.
- AgentData: Hosted MCP at mcp.agentdata.run, npm agentdata-mcp-server, seven tools, free.
- BuiltWith: MCP API listed among paid APIs; Free API limited to groups.
claude mcp add agentdata --transport http https://mcp.agentdata.run/mcp \
--header "Authorization: Bearer YOUR_API_KEY"Source: api.builtwith.com API list; blog.builtwith.com/2026/02/25/llms-and-mcp/
Who moves from BuiltWith to AgentData
You run BuiltWith lookups a dozen times a day and never bought the API because $295 a month for two technology reports never penciled out for a five-person shop. AgentData gives you the same “what does this site run” answer, plus who to email about it, at $0.
Your list is “e-commerce companies on Shopify with Klaviyo”. BuiltWith builds it; then you pay a contact vendor to fill in the emails. AgentData returns the list with verified emails and the marketing lead's name in the same query.
You wanted builtwith.com/plans to have an API tier under $295 and it doesn't. AgentData's MCP server is one claude mcp add away, the REST API is free at 1,000 lookups a day, and the response already has the fields your agent needs to decide what to do next.
Switching from BuiltWith
- Export your BuiltWith lists. From any Technology or Keyword report, Export → CSV. Keep the Domain column; that's the join key.
- Enrich in AgentData. Upload the domain column to a list, or loop GET /api/v1/lookup?domain= over it (1,000 a day free; larger volumes in batches across days). You get back the stack, the company profile, verified emails and people.
- Run both for a month, then cancel. BuiltWith is month to month with pro-rated refunds on downgrades, so nothing is lost by keeping it during the switch. Compare the tech detections on 50 domains you know well before you decide.
Field map: BuiltWith → AgentData
Where BuiltWith fits better
- You need long-tail technology coverage. 127,643 technologies is two orders of magnitude more than we track. Niche plugins, ad-tech vendors, hosting sub-products: BuiltWith.
- You need history. 18 years of trends and first-detected dates going back to the 2000s. We started crawling in 2026.
- You need market-share reporting by country. trends.builtwith.com is the reference dataset for “CMS market share in Germany”; our /tech/[slug] pages show current counts by sector and size only.
- You need native CRM sync. Six CRM integrations included on every BuiltWith plan; we offer CSV and API.
We would rather you pick the right tool than ours for the wrong reasons. If two of those four describe you, BuiltWith is the right tool, and you can still use AgentData for the emails and people it doesn't verify.
Frequently asked questions
Related reading
Switching from BuiltWith takes an afternoon.
133M companies. 4,077 technologies. 16M email addresses. Free.