# TechnologyChecker, free, GET /v1/signals/whitespace: Company discovery API

> Find domains that run a qualifying anchor technology but no tool at all in a target category — greenfield prospecting, the inverse of adoption. Costs 1 credit.

TechnologyChecker's company discovery API on its Free plan. It costs $0.00 per 1,000 companies. It returns 4 of the 13 key fields we check: Industry, Type and status, Employees, Headquarters.
We rank 533 plans by price. [Deepline's top-up](https://datacircle.dev/company-discovery-apis/deepline/top-up/llms.txt) costs the least per 1,000 companies. Deepline's company discovery API costs nothing beyond the plan price.
[GetProspect](https://datacircle.dev/company-discovery-apis/getprospect/49-monthly/llms.txt), [Hunter](https://datacircle.dev/company-discovery-apis/hunter/49-monthly-starter-post-discover/llms.txt) and [Skrapp](https://datacircle.dev/company-discovery-apis/skrapp/349-monthly/llms.txt) are the best company discovery API providers in our benchmark.

- This page: https://datacircle.dev/company-discovery-apis/technologychecker/free-get-v1-signals-whitespace
- [Best company discovery API in 2026](https://datacircle.dev/best-company-discovery-api.txt)
- Get it: https://technologychecker.io/pricing
- Request: `GET https://api.technologychecker.io/v1/signals/whitespace`
- API key: with the plan, on https://technologychecker.io/pricing
- Its API docs: https://technologychecker.io/docs/api-reference/signals/category-whitespace-api
- Sold by: TechnologyChecker (https://technologychecker.io)
- Checked: 2026-10-26

## In the answer

- Completeness: 31%
- Industry: ✓
- Type and status: ✓
- Employees: ✓
- Headquarters: ✓

## Price

- $ per 1,000 companies: $0.00
- Per: page of 1,000
- Billing: free

## Aggregators

- Aggregators: none

## Charges

- Most per search: 1,001,000
- Also pays for: Signal types index · List alerts API · Create alert API · Get alert API · Update alert API · Delete alert API · Test alert delivery API: roughly 10 per hour per key · Alert delivery log API · Create audience API: uploads are free · List audiences API · Get audience API · Update audience API: renaming is free · Delete audience API · List audience members API · Search technologies for lead lists API · Technology ID map API · Preview lead list count API · List lead lists API · Preview lead list API · Export lead list API · Delete lead list API · from the same budget: Domain lookup · Domain history · Domain tech changes · Find domains by technology · Technology lookup / search · Technology stats API · Technology usage trends API · Market share · Get companies by technology · Company lookup · Company search · Batch company lookup (1 per domain) · Adoption and churn signals API · Competitive switch API · Audience technology report · Audience breakdown · Segment technology stats · Build a computed audience · Live technology lookup · AI extractor · Create lead list API (1 per delivered row) · Export signals to CSV API (1 per exported row) · Churn validation · Audience refresh crawl · Alert crawl cadence

## Not found

- $ per 1,000: $0.00

## In their words

- Their pitch: Find domains that run a qualifying anchor technology but no tool at all in a target category — greenfield prospecting, the inverse of adoption. Costs 1 credit.

## Data

- Freshness: stored
- Keep data: Cached data must be refreshed at intervals consistent with your subscription plan
- Use data: You may integrate API data into your internal business applications, CRM systems, and workflows [...] You may not redistribute raw API data to third parties or make it publicly accessible without our written consent [...] You may not use API data to create a competing technology detection service or database [...] You must comply with all applicable data protection laws when processing personal data obtained through the API [...] The following activities are strictly prohibited: [...] Reselling, redistributing, sublicensing, or otherwise making the Service or its data available to third parties without our prior written consent [...] Using the Service or its data to build a competing product, service, or database [...] Using the Service to send unsolicited commercial communications (spam), including bulk emails, cold calls, or messages to contacts obtained through the Service without a legitimate legal basis

## Plan

- Pay: $0
- You get: 100 credits a month
- Enough for: 100 pages a month
- Expires: at the monthly reset, credits don't roll over

## Rate limit

- Per second: 0.17
- Batch: 1

## Speed

- Answer: in the call

## The call

- You send: missing_category_id, one of technology_id, technology or category_id. Optional: min_confidence, limit, offset, country, city, state, industry, industry_code, employees, company_type, founded_min, founded_max, company, has_email, has_phone, social, language, web_country, segment_id
- Method: GET
- Path: /v1/signals/whitespace

## About the plan

- Plan: Free
- Who can get it: anyone 18 or over, for individual evaluation: the free plan may not be used for commercial-scale operations

## The 11 fields the plan's answer can hold

domain, company name, industry, industry code, employee count range, country, city, state, founded, company type, total results

## TechnologyChecker's plans (6)

- [TechnologyChecker, free, GET /v1/signals/whitespace](https://datacircle.dev/company-discovery-apis/technologychecker/free-get-v1-signals-whitespace/llms.txt): $0.00 per 1,000, 31% complete, stored
- [TechnologyChecker, $89 monthly, Pro, GET /v1/signals/whitespace](https://datacircle.dev/company-discovery-apis/technologychecker/89-monthly-pro-get-v1-signals-whitespace/llms.txt): $0.0089 per 1,000, 31% complete, stored
- [TechnologyChecker, $249 monthly, Scale, GET /v1/signals/whitespace](https://datacircle.dev/company-discovery-apis/technologychecker/249-monthly-scale-get-v1-signals-whitespace/llms.txt): $0.005 per 1,000, 31% complete, stored
- [TechnologyChecker, $890 yearly, Pro, GET /v1/signals/whitespace](https://datacircle.dev/company-discovery-apis/technologychecker/890-yearly-pro-get-v1-signals-whitespace/llms.txt): $0.0074 per 1,000, 31% complete, stored
- [TechnologyChecker, $2,490 yearly, Scale, GET /v1/signals/whitespace](https://datacircle.dev/company-discovery-apis/technologychecker/2490-yearly-scale-get-v1-signals-whitespace/llms.txt): $0.0042 per 1,000, 31% complete, stored
- [TechnologyChecker, contact us, Enterprise, GET /v1/signals/whitespace](https://datacircle.dev/company-discovery-apis/technologychecker/contact-us-enterprise-get-v1-signals-whitespace/llms.txt): 31% complete, stored

## TechnologyChecker's calls for this API (8)

- `GET /v1/signals/{type}`: [TechnologyChecker, free, GET /v1/signals/{type}](https://datacircle.dev/company-discovery-apis/technologychecker/free-get-v1-signals-type/llms.txt)
- `GET /v1/signals/whitespace`: [TechnologyChecker, free, GET /v1/signals/whitespace](https://datacircle.dev/company-discovery-apis/technologychecker/free-get-v1-signals-whitespace/llms.txt)
- `GET /v1/signals/switch`: [TechnologyChecker, free, GET /v1/signals/switch](https://datacircle.dev/company-discovery-apis/technologychecker/free-get-v1-signals-switch/llms.txt)
- `POST /v1/leads/create`: [TechnologyChecker, free, POST /v1/leads/create](https://datacircle.dev/company-discovery-apis/technologychecker/free-post-v1-leads-create/llms.txt)
- `GET /v1/signals/{type}/export`: [TechnologyChecker, free, GET /v1/signals/{type}/export](https://datacircle.dev/company-discovery-apis/technologychecker/free-get-v1-signals-type-export/llms.txt)
- `GET /v1/technology/name/{name}/domains`: [TechnologyChecker, free, GET /v1/technology/name/{name}/domains](https://datacircle.dev/company-discovery-apis/technologychecker/free-get-v1-technology-name-name-domains/llms.txt)
- `GET /v1/technology/{id}/companies`: [TechnologyChecker, free, GET /v1/technology/{id}/companies](https://datacircle.dev/company-discovery-apis/technologychecker/free-get-v1-technology-id-companies/llms.txt)
- `GET /v1/companies`: [TechnologyChecker, free, GET /v1/companies](https://datacircle.dev/company-discovery-apis/technologychecker/free-get-v1-companies/llms.txt)

## TechnologyChecker's APIs (3)

- [TechnologyChecker: company discovery API pricing, 6 plans, GET /v1/signals/whitespace](https://datacircle.dev/company-discovery-apis/technologychecker/free-get-v1-signals-whitespace/llms.txt)
- [TechnologyChecker: company enrichment API pricing, 6 plans, POST /v1/companies/batch](https://datacircle.dev/company-enrichment-apis/technologychecker/free-post-v1-companies-batch/llms.txt)
- [TechnologyChecker: company enrichment API pricing, 6 plans, GET /v1/company/{domain}](https://datacircle.dev/company-enrichment-apis/technologychecker/free-get-v1-company-domain/llms.txt)
- [TechnologyChecker: tech stack API pricing, 6 plans, GET /v1/domain/{domain}/changes](https://datacircle.dev/company-technology-apis/technologychecker/free-get-v1-domain-domain-changes/llms.txt)
- [TechnologyChecker: tech stack API pricing, 6 plans, GET /v1/domain/{domain}/history](https://datacircle.dev/company-technology-apis/technologychecker/free-get-v1-domain-domain-history/llms.txt)
- [TechnologyChecker: tech stack API pricing, 6 plans, GET /v1/domain/{domain}](https://datacircle.dev/company-technology-apis/technologychecker/free-get-v1-domain-domain/llms.txt)
- [TechnologyChecker: tech stack API pricing, 6 plans, POST /v1/technology-lookup-live](https://datacircle.dev/company-technology-apis/technologychecker/free-free-post-v1-technology-lookup-live/llms.txt)
- [TechnologyChecker: tech stack API pricing, 6 plans, GET /v1/technology-lookup-live](https://datacircle.dev/company-technology-apis/technologychecker/free-free-get-v1-technology-lookup-live/llms.txt)

## TechnologyChecker: company discovery API alternatives

- [graph8, $499 monthly](https://datacircle.dev/company-discovery-apis/graph8/499-monthly/llms.txt): $0.00012 per 1,000, 69% complete, stored
- [Argorant, $949 monthly](https://datacircle.dev/company-discovery-apis/argorant/949-monthly/llms.txt): $0.0018 per 1,000, 62% complete, stored
- [Hunter, $6,935 yearly, Data Platform, 950,000 Search credits, POST /discover](https://datacircle.dev/company-discovery-apis/hunter/6935-yearly-data-platform-950000-search-credits-post-discover/llms.txt): $0.0027 per 1,000, 54% complete, stored
- [The Swarm, $96,000 yearly, Enterprise 20000, POST /v3/companies/search](https://datacircle.dev/company-discovery-apis/the-swarm/96000-yearly-enterprise-20000-post-v3-companies-search/llms.txt): $0.0031 per 1,000, 0% complete, stored

## Sources

From each provider's own pricing page and docs, and from what providers tell us. We read this row from these pages on 2026-10-26.

- https://technologychecker.io/docs/api-reference/credits
- https://technologychecker.io/docs/api-reference/openapi.json
- https://technologychecker.io/docs/api-reference/rate-limits
- https://technologychecker.io/docs/api-reference/signals/category-whitespace-api
- https://technologychecker.io/pricing
- https://technologychecker.io/terms-of-use