> ## Documentation Index > Fetch the complete documentation index at: https://technologychecker.io/docs/llms.txt > Use this file to discover all available pages before exploring further. # Segment technology stats API > How much of one technology's live footprint belongs to a slice of companies. Returns three self-consistent counts. Costs 1 credit, cache hits included. ## Frequently asked questions `live_active_domains` is every domain currently running the technology. `matched_domains` is the subset with a matched company record. `segment_domains` is the subset of *those* that pass your predicates. They come from a single pass, so `segment_domains ≤ matched_domains ≤ live_active_domains` always holds and the ratios are internally consistent. A request with a technology but no predicate is rejected with `MISSING_SEGMENT`. Without a predicate this endpoint would just re-derive global technology stats at much greater cost — use [the technology stats endpoint](/docs/api-reference/market-intelligence/technology-stats-api) for that. Yes. Results are cached for 24 hours, and a cache hit still costs 1 credit — the response tells you with `cache.hit` and `cache.age_seconds`. This is deliberate: a change to our caching should never become a silent change to your price. Yes, pass `segment_id`. It is mutually exclusive with inline firmographic parameters. Note that only firmographic audiences replay here — other kinds are rejected with a pointer to [the technology report](/docs/api-reference/audiences/audience-technologies-api), which is the right endpoint for their per-technology numbers. A broad segment over a very large technology can exceed the 30-second query limit. It is surfaced as `SEGMENT_QUERY_TIMEOUT` and is never retried server-side. Narrow the segment — add an employee band, an industry or a city. ## OpenAPI ````yaml GET /v1/segments/stats openapi: 3.1.0 info: title: TechnologyChecker API description: >- Discover technology stacks, track market trends, and enrich data with company intelligence. version: 1.0.0 contact: name: TechnologyChecker Support email: support@technologychecker.io url: https://technologychecker.io servers: - url: https://api.technologychecker.io description: Production security: - bearerAuth: [] tags: - name: Domain technologies description: Look up technologies detected on any domain - name: Technology data description: Search, look up, and get details on tracked technologies - name: Market intelligence description: Technology stats, trends, and market share - name: Company data description: Firmographic and company intelligence - name: Live detection description: Real-time technology detection with browser rendering - name: Signals description: >- Intent signals derived from technology state transitions: who adopted, who churned, who switched, and who has a gap in their stack. - name: Alerts description: >- Saved signal queries delivered to your webhook. Every signal you can query, you can subscribe to. - name: Audiences description: >- Saved groups of domains — uploaded lists or computed recipes — that you can profile, slice and monitor. - name: Lead lists description: >- Build and export targeted domain lists combining technology detection with company data. paths: /v1/segments/stats: get: tags: - Audiences summary: Segment technology stats API description: >- How much of one technology's live footprint belongs to a slice of companies. Returns three self-consistent counts from a single pass, so `segment_domains ≤ matched_domains ≤ live_active_domains` always holds: - `live_active_domains` — domains currently running the technology - `matched_domains` — of those, the ones with a matched company record - `segment_domains` — of those, the ones passing your predicates Requires a technology scope and **at least one** firmographic predicate, or a saved `segment_id`. Without a predicate this would just re-derive global stats expensively, so it is rejected. Results are cached for 24 hours. **Cache hits still cost 1 credit** — a cache tuning must never become a silent price change. operationId: getSegmentTechnologyStats parameters: - name: technology_id in: query required: false description: The technology to measure. Provide this or `technology`. schema: type: integer example: 2184 - name: technology in: query required: false description: The technology to measure, by exact name. schema: type: string example: Shopify - $ref: '#/components/parameters/FirmoCountry' - $ref: '#/components/parameters/FirmoCity' - $ref: '#/components/parameters/FirmoState' - $ref: '#/components/parameters/FirmoIndustry' - $ref: '#/components/parameters/FirmoIndustryCode' - $ref: '#/components/parameters/FirmoEmployees' - $ref: '#/components/parameters/FirmoCompanyType' - $ref: '#/components/parameters/FirmoFoundedMin' - $ref: '#/components/parameters/FirmoFoundedMax' - $ref: '#/components/parameters/WebHasEmail' - $ref: '#/components/parameters/WebHasPhone' - $ref: '#/components/parameters/WebSocial' - $ref: '#/components/parameters/WebLanguage' - $ref: '#/components/parameters/WebCountry' - $ref: '#/components/parameters/SegmentId' responses: '200': description: Three self-consistent counts plus the share of matched companies content: application/json: schema: type: object properties: success: type: boolean example: true data: type: object properties: technology: type: object properties: id: type: integer example: 2184 name: type: string example: Shopify category: type: string nullable: true example: Ecommerce Platforms segment: type: object properties: applied: type: object additionalProperties: true example: country: united states employees: 51-200 coverage_note: type: string stats: type: object properties: live_active_domains: type: integer example: 2314529 matched_domains: type: integer example: 578632 segment_domains: type: integer example: 32311 segment_share_of_matched: type: number format: float nullable: true example: 0.0559 cache: type: object properties: hit: type: boolean example: false age_seconds: type: integer example: 0 generated_at: type: string '400': $ref: '#/components/responses/BadRequest' '401': $ref: '#/components/responses/Unauthorized' '402': $ref: '#/components/responses/PaymentRequired' '403': $ref: '#/components/responses/Forbidden' '404': $ref: '#/components/responses/NotFound' '429': $ref: '#/components/responses/RateLimited' '503': $ref: '#/components/responses/QueryTimeout' components: parameters: FirmoCountry: name: country in: query required: false description: Filter to companies in this country (case-insensitive). schema: type: string example: united states FirmoCity: name: city in: query required: false description: Filter to companies in this city (case-insensitive). schema: type: string FirmoState: name: state in: query required: false description: Filter to companies in this state or region (case-insensitive). schema: type: string FirmoIndustry: name: industry in: query required: false description: Filter to companies in this industry (case-insensitive). schema: type: string example: retail FirmoIndustryCode: name: industry_code in: query required: false description: Filter by exact LinkedIn industry code. schema: type: integer FirmoEmployees: name: employees in: query required: false description: >- Filter by exact LinkedIn employee band. Unknown bands are rejected with `INVALID_EMPLOYEE_BAND` and the allowed list. schema: type: string example: 51-200 FirmoCompanyType: name: company_type in: query required: false description: Filter by exact company type. schema: type: string example: Privately Held FirmoFoundedMin: name: founded_min in: query required: false description: Only companies founded in or after this year. schema: type: integer minimum: 1800 maximum: 2025 FirmoFoundedMax: name: founded_max in: query required: false description: Only companies founded in or before this year. schema: type: integer minimum: 1800 maximum: 2025 WebHasEmail: name: has_email in: query required: false description: >- Filter to domains where the crawler found (or did not find) an email address. `false` is a real filter, not a no-op. schema: type: boolean WebHasPhone: name: has_phone in: query required: false description: >- Filter to domains where the crawler found (or did not find) a phone number. schema: type: boolean WebSocial: name: social in: query required: false description: Filter to domains publishing a profile on this platform. schema: type: string enum: - linkedin - x - facebook - instagram - youtube - github - tiktok - discord - reddit - crunchbase - slack example: instagram WebLanguage: name: language in: query required: false description: Filter by the site's primary language. schema: type: string example: de WebCountry: name: web_country in: query required: false description: >- Filter by the country the site declares in its schema.org markup. Accepts ISO-2, English name or common variants. schema: type: string example: USA SegmentId: name: segment_id in: query required: false description: >- Apply a saved audience instead of inline filters. Filter audiences replay their firmographic predicates; list audiences restrict rows to their member domains. Mutually exclusive with inline firmographic parameters. schema: type: string example: seg_8f3a2c1b responses: BadRequest: description: Invalid or missing parameters content: application/json: schema: $ref: '#/components/schemas/ApiError' example: success: false error: code: VALIDATION_ERROR message: >- Provide exactly one scope: technology_id, technology or category_id. Unauthorized: description: Missing or invalid API key content: application/json: schema: $ref: '#/components/schemas/ApiError' PaymentRequired: description: Not enough credits, or the plan does not include this feature content: application/json: schema: $ref: '#/components/schemas/ApiError' example: success: false error: code: INSUFFICIENT_CREDITS message: Insufficient credits for this request. details: required: 1 available: 0 Forbidden: description: The plan does not allow this action, or a plan limit was reached content: application/json: schema: $ref: '#/components/schemas/ApiError' example: success: false error: code: PLAN_LIMIT message: >- Your plan allows up to 2 saved audiences. Delete one to create another. NotFound: description: Resource not found content: application/json: schema: $ref: '#/components/schemas/ApiError' RateLimited: description: Rate limit exceeded content: application/json: schema: $ref: '#/components/schemas/ApiError' QueryTimeout: description: >- The query exceeded the 30-second server-side limit. Narrow the query and retry. content: application/json: schema: $ref: '#/components/schemas/ApiError' example: success: false error: code: SEGMENT_QUERY_TIMEOUT message: The segment query exceeded the 30s server-side limit. details: suggestion: >- Narrow the segment — add an employees band, industry, or city — and try again. schemas: ApiError: type: object properties: success: type: boolean example: false error: type: object properties: code: type: string example: UNAUTHORIZED message: type: string example: Missing or invalid API key securitySchemes: bearerAuth: type: http scheme: bearer description: >- API key in format `tapi_live_[32-char]` (live) or `tapi_test_[32-char]` (test) ````