runsonwhat API
Company tech stacks, the companies behind every tool, and who starts and stops using it, from public evidence: DNS and email records, certificates, website code, a real-browser crawl and subprocessor lists. Every match says where it was found.
Get started
1. Sign in and create a key on your API page. The key is shown once.
2. Get credits: email hello@runsonwhat.com.
3. Make your first call:
Authentication
Send your key as Authorization: Bearer row_live_… or in an x-api-key header. Keys never go in the URL, so they don't end up in logs. You can have five keys and revoke any of them on your API page.
Credits
You pay only for results returned. Errors, and companies we don't have yet, cost nothing. When your balance can't pay for a full page, the page is cut to what it can pay for.
Limits and headers
60 requests per 10 seconds per key and 50,000 rows a day per account (resets 00:00 UTC). Need more? Email hello@runsonwhat.com. Every response carries:
Pagination
List endpoints return pagination.next_cursor. Pass it back as cursor for the next page; when has_more is false you have everything. Company lists come in a stable order, so paging never skips or repeats a company.
Errors
Errors return { "error": { "code": "…", "message": "…" } } and cost nothing.
What counts as a match
A tool is listed only with direct public evidence or high confidence; weak hints don't count, and a tool that leaves no public trace can't be seen. Read the methodology.
Endpoints
- GET /api/v1/companies/{domain}: Get a company's tech stack. Every tool we found for a company, with where each was found, the adoption date where a certificate proves it, the company profile, recent starts and stops, and open roles from its public job board.
Cost: 1 credit. Companies we don't have yet return 404 and cost nothing.
- GET /api/v1/tools/{tool}/companies: List companies using a tool. Companies currently using a tool, with their profile and how the tool was found. Follow next_cursor to read the whole list.
Cost: 1 credit per company returned.
- GET /api/v1/changes: List starts and stops. Companies that started using a tool, stopped, or came back, newest first. A stop is recorded only when two checks by the same method disagree, so a change in how we scan never reads as churn. Pass tool, category or domain.
Cost: 2 credits per change returned.
- GET /api/v1/tools: List the tools we track. Tool ids, names, categories, vendor domains and how many companies use each, plus the list of categories.
Cost: no credits.
- GET /api/v1/usage: Get your credits and usage. Your balance, limits, prices and usage per day and endpoint.
Cost: no credits.
OpenAPI 3.1 description