generated: '2026-08-14' method: searched source: https://api.builtwith.com/domain-api, https://api.builtwith.com/llms.txt docs: https://api.builtwith.com/domain-api limit_count: 7 name: BuiltWith API Rate Limits description: Rate limits and throttling policies for the BuiltWith API platform across all available endpoints. specificationVersion: '0.1' url: https://api.builtwith.com/ rateLimits: - name: Domain API Rate Limit description: Concurrent request and per-second rate limits for the BuiltWith Domain API. api: Domain API endpoint: https://api.builtwith.com/v22/api.{format} limits: - type: concurrent max: 8 description: Maximum 8 concurrent requests at any one time - type: per-second max: 10 description: Maximum 10 requests per second enforcement: - type: http-status code: 429 description: Returns HTTP 429 Too Many Requests when limits are exceeded headers: - name: X-RATELIMIT-CURRENT-CONCURRENT example: 2 description: Current number of concurrent requests in flight - name: X-RATELIMIT-CURRENT-PERSECOND example: 2 description: Current requests per second being made - name: X-RATELIMIT-LIMIT-CONCURRENT example: 8 description: The maximum concurrent rate before 429 errors - name: X-RATELIMIT-LIMIT-PERSECOND example: 10 description: The maximum requests per second before 429 errors - name: X-API-CREDITS-AVAILABLE description: Total API credits available on the account - name: X-API-CREDITS-USED description: API credits used in the current billing period - name: X-API-CREDITS-REMAINING description: API credits remaining in the current billing period errorFormat: status: 429 body: '{"error":"Rate limit exceeded","maxConcurrentRequests":8,"maxRequestsPerSecond":1,"currentConcurrentRequests":0,"currentRequestsInWindow":1,"retryAfterSeconds":1}' retryHint: retryAfterSeconds notes: - Contact BuiltWith for dedicated endpoints to remove rate limits for high-volume use cases - Live per-account ceilings are also reported by GET /whoamiv1/api.json under rate_limits (requests_per_second, concurrency) - name: Free API Rate Limit description: Rate limit applied to the BuiltWith Free API tier. api: Free API endpoint: https://api.builtwith.com/free1/api.{format} limits: - type: per-second max: 1 description: Maximum 1 request per second enforcement: - type: http-status code: 429 description: Returns HTTP 429 Too Many Requests when limits are exceeded notes: - Free API is available to all registered users at no cost - Upgrade to a paid plan for higher rate limits - name: Lists API Rate Limit description: Rate limits for the BuiltWith Lists API used for technology-based website lists. api: Lists API endpoint: https://api.builtwith.com/lists12/api.{format} limits: - type: credits description: Requests consume credits from the account balance; exact per-request credit cost depends on plan notes: - Credit costs vary by query complexity and result size - Account credit usage is tracked in the dashboard - name: Credit System description: BuiltWith uses a credit-based system for API usage across paid plans, with credits consumed per request. creditSystem: teamPlanCredits: 1200000 teamPlanPeriod: yearly teamPlanMonthlyCredits: 100000 creditTracking: - header: X-API-CREDITS-AVAILABLE - header: X-API-CREDITS-USED - header: X-API-CREDITS-REMAINING notes: - Credits reset on a monthly or annual basis depending on the plan - Some endpoints (e.g., TRUST parameter in Domain API) consume additional credits - Dedicated plans available for enterprise-level credit needs - name: Bulk Domain API Limits description: Rate limits and job constraints for the BuiltWith Bulk Domain API. api: Bulk Domain API endpoint: https://api.builtwith.com/v22/domain/bulk notes: - Bulk jobs are submitted via POST and polled for status - Rate limits apply per account; contact BuiltWith for high-volume batch processing - Results available via GET /v22/domain/bulk/{job_id} - name: MCP Registry API Rate Limit description: Free MCP registry search endpoint, rate limited more tightly than the general API. api: MCP Registry API endpoint: https://api.builtwith.com/mcp2/api.json limits: - type: per-second max: 1 description: Maximum 1 request per second per API key headers: - name: X-TOTAL-COUNT description: Total matching registry entries - name: X-OFFSET description: Current pagination offset - name: X-PAGE-SIZE description: Results per page (100) - name: X-HAS-MORE description: Whether more pages remain notes: - Free - no API credits used - Stricter than the general API rate limit because the endpoint is free - name: Live Feed API Limits description: WebSocket connection limits for the BuiltWith Live Feed API. api: Live Feed API endpoint: wss://sync.builtwith.com/wss/ limits: - type: connection description: Real-time WebSocket stream; connection limits apply per account subscriptionLimits: - plan: Basic max: 2 description: Up to 2 technology subscriptions per API key - plan: Pro max: 50 description: Up to 50 technology subscriptions per API key notes: - WebSocket protocol requires persistent connection management - Disconnects and reconnects count against connection limits - Trial and expired accounts receive obfuscated domain names rather than being blocked authentication: methods: - name: Query Parameter description: Pass the API key as a KEY query parameter in every request example: "https://api.builtwith.com/v22/api.json?KEY=your-api-key&LOOKUP=example.com" - name: HTTP Header description: Pass the API key as an Authorization header format: "Authorization: API your-api-key" security: - HTTPS required for all endpoints - API keys must be kept secret; never expose in client-side code - Rotate API keys if compromised via the account dashboard