Domain Age Checker

Give it a list of domains and get back registration date, expiration date, age, and time remaining — instantly. Send a list of domain names and this tool tells you exactly how old each one is, when it was first registered, when it expires, and how much time is left before expiration. Great for spotting brand-new suspicious domains, researching competitors, or evaluating domains before buying or linking to them. Works with over 100 domain extensions worldwide. Pay-per-call at $0.01 USDC over x402 on Base or Solana — no account, no API key. OpenAPI 3.1.0; 1 operation(s): POST /lookup.

OpenAPI Specification

done-domain-age-checker-openapi.yml Raw ↑
openapi: 3.1.0
info:
  title: Domain Age Checker
  description: Send a list of domain names and this tool tells you exactly how old each one is, when it was first registered,
    when it expires, and how much time is left before expiration. Great for spotting brand-new suspicious domains, researching
    competitors, or evaluating domains before buying or linking to them. Works with over 100 domain extensions worldwide.
  version: 1.0.0
  contact:
    name: _done
    url: https://forms.gle/5KzuSFH7p8hHtDmz7
    email: info@underscoredone.com
  x-openapi-url: https://domain-age-checker.underscoredone.com/openapi.json
  x-logo:
    url: https://underscoredone.com/logo.png
    altText: _done
  x-guidance: POST a JSON body with a 'domains' list of domain name strings (plain domains or full URLs both work). Each result
    includes 'domainName', 'age' as a human-readable string, 'registrationDate', 'lastUpdateDate', 'expirationDate', 'expiringIn'
    as a human-readable string, and 'status' which is 'success' or 'error'. If WHOIS data cannot be retrieved for a domain,
    that entry will have status 'error' and an 'error' field explaining why — other domains in the batch still return normally.
    Strip URLs down to bare domains before lookup. Batch size is capped at 50 domains per request.
  x-ai-instructions: POST a JSON body with a 'domains' list of domain name strings (plain domains or full URLs both work).
    Each result includes 'domainName', 'age' as a human-readable string, 'registrationDate', 'lastUpdateDate', 'expirationDate',
    'expiringIn' as a human-readable string, and 'status' which is 'success' or 'error'. If WHOIS data cannot be retrieved
    for a domain, that entry will have status 'error' and an 'error' field explaining why — other domains in the batch still
    return normally. Strip URLs down to bare domains before lookup. Batch size is capped at 50 domains per request.
  x-provider: _done — single-purpose utility APIs for developers and AI agents. Pay per call with USDC on Base Mainnet or
    Solana Mainnet.
  x-pricing:
    model: pay-per-call
    currency: USDC
    network: Base Mainnet or Solana Mainnet
    price: $0.01
  x-keywords: []
  x-category: domain age
  x-provider-url: https://underscoredone.com
  x-agentcash-auth:
    mode: paid
  x-402:
    price: $0.01
    network: eip155:8453
    asset: '0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913'
    pay_to: '0xE9740820225B3918b4ddd1292C7cA4Ca0e2C2F08'
    facilitator: https://api.cdp.coinbase.com/platform/v2/x402
    scheme: exact
    description: Send a list of domain names and this tool tells you exactly how old each one is, when it was first registered,
      when it expires, and how much time is left before expiration. Great for spotting brand-new suspicious domains, researching
      competitors, or evaluating domains before buying or linking to them. Works with over 100 domain extensions worldwide.
    mime_type: application/json
    networks:
    - network: eip155:8453
      asset: '0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913'
      pay_to: '0xE9740820225B3918b4ddd1292C7cA4Ca0e2C2F08'
    - network: solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp
      asset: EPjFWdd5AufqSSqeM2qN1xzybapC8G4wEGGkZwyTDt1v
      pay_to: 8ugAWAXDB8V18kiUrGZTq1oMvU3C6Fxs8hfC6rvzQT3b
paths:
  /lookup:
    post:
      tags:
      - domain age
      - domain age checker
      - domain
      - how old is a domain
      - domain registration date
      - domain expiry date
      - domain creation date
      - whois age
      - domain research
      - domain due diligence
      - domain valuation
      - expiration date lookup
      - new domain detection
      - domain history
      summary: Check how old a list of domains is and when they expire
      description: Check how old a list of domains is, when they were registered, and when they expire.
      operationId: handler_lookup_post
      requestBody:
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/DomainLookupRequest'
        required: true
      responses:
        '200':
          description: Successful response
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/DomainLookupResponse'
              examples:
                success:
                  summary: Successful response
                  value:
                    api_version: 1.0.0
                    results:
                    - domainName: google.com
                      age: 26 Years 10 Months 12 Days
                      registrationDate: '1997-09-15'
                      lastUpdateDate: '2024-09-07'
                      expirationDate: '2028-09-14'
                      expiringIn: 3 Years 1 Month 18 Days
                      status: success
                    - domainName: openai.com
                      age: 9 Years 3 Months 5 Days
                      registrationDate: '2015-04-18'
                      lastUpdateDate: '2024-11-01'
                      expirationDate: '2026-04-18'
                      expiringIn: 11 Months 22 Days
                      status: success
                    total: 2
                    succeeded: 2
                    failed: 0
                    processed_at: '2024-07-27T14:22:01Z'
        '422':
          description: Unprocessable — a required field is missing or the wrong type. Check the detail field for specifics.
          content:
            application/json:
              schema:
                type: object
                properties:
                  detail:
                    type: array
        '402':
          description: Payment required. Send a signed USDC payment on Base Mainnet or Solana Mainnet using the x402 protocol.
          headers:
            X-Payment-Response:
              description: x402 payment challenge — base64-encoded JSON with payment details.
              schema:
                type: string
        '400':
          description: Bad request — your input failed validation or could not be processed. Check the detail field for specifics.
          content:
            application/json:
              schema:
                type: object
                properties:
                  detail:
                    type: string
      x-ai-instructions: POST a JSON body with a 'domains' list of domain name strings (plain domains or full URLs both work).
        Each result includes 'domainName', 'age' as a human-readable string, 'registrationDate', 'lastUpdateDate', 'expirationDate',
        'expiringIn' as a human-readable string, and 'status' which is 'success' or 'error'. If WHOIS data cannot be retrieved
        for a domain, that entry will have status 'error' and an 'error' field explaining why — other domains in the batch
        still return normally. Strip URLs down to bare domains before lookup. Batch size is capped at 50 domains per request.
      x-guidance: POST a JSON body with a 'domains' list of domain name strings (plain domains or full URLs both work). Each
        result includes 'domainName', 'age' as a human-readable string, 'registrationDate', 'lastUpdateDate', 'expirationDate',
        'expiringIn' as a human-readable string, and 'status' which is 'success' or 'error'. If WHOIS data cannot be retrieved
        for a domain, that entry will have status 'error' and an 'error' field explaining why — other domains in the batch
        still return normally. Strip URLs down to bare domains before lookup. Batch size is capped at 50 domains per request.
      x-payment-info:
        price:
          fixed:
            mode: fixed
            currency: USD
            amount: '0.01'
        protocols:
        - x402: {}
components:
  schemas:
    DomainLookupRequest:
      properties:
        domains:
          items:
            type: string
          type: array
          title: Domains
          description: A list of domain names you want to look up. You can include plain domains like 'example.com' or full
            web addresses like 'https://example.com/page' — both work. Maximum 50 domains per request.
      type: object
      required:
      - domains
      title: DomainLookupRequest
      example:
        domains:
        - google.com
        - openai.com
        - github.com
    DomainLookupResponse:
      properties:
        api_version:
          type: string
          title: Api Version
          description: API version
          default: 1.0.0
        results:
          items:
            additionalProperties: true
            type: object
          type: array
          title: Results
          description: One result entry per domain you submitted, in the same order.
        total:
          type: integer
          title: Total
          description: Total number of domains you submitted.
        succeeded:
          type: integer
          title: Succeeded
          description: How many domains returned successful registration data.
        failed:
          type: integer
          title: Failed
          description: How many domains could not be looked up.
        processed_at:
          type: string
          title: Processed At
          description: The exact date and time this lookup was completed.
      type: object
      required:
      - results
      - total
      - succeeded
      - failed
      - processed_at
      title: DomainLookupResponse
      example:
        api_version: 1.0.0
        failed: 0
        processed_at: '2024-07-27T14:22:01Z'
        results:
        - age: 26 Years 10 Months 12 Days
          domainName: google.com
          expirationDate: '2028-09-14'
          expiringIn: 3 Years 1 Month 18 Days
          lastUpdateDate: '2024-09-07'
          registrationDate: '1997-09-15'
          status: success
        - age: 9 Years 3 Months 5 Days
          domainName: openai.com
          expirationDate: '2026-04-18'
          expiringIn: 11 Months 22 Days
          lastUpdateDate: '2024-11-01'
          registrationDate: '2015-04-18'
          status: success
        succeeded: 2
        total: 2
    HTTPValidationError:
      properties:
        detail:
          items:
            $ref: '#/components/schemas/ValidationError'
          type: array
          title: Detail
      type: object
      title: HTTPValidationError
    ValidationError:
      properties:
        loc:
          items:
            anyOf:
            - type: string
            - type: integer
          type: array
          title: Location
        msg:
          type: string
          title: Message
        type:
          type: string
          title: Error Type
        input:
          title: Input
        ctx:
          type: object
          title: Context
      type: object
      required:
      - loc
      - msg
      - type
      title: ValidationError
  securitySchemes:
    siwx:
      type: apiKey
      in: header
      name: SIGN-IN-WITH-X
      description: CAIP-122 wallet signature for repeat access after payment
servers:
- url: https://domain-age-checker.underscoredone.com
  description: Production
tags:
- name: domain age
- name: domain age checker
- name: domain
- name: how old is a domain
- name: domain registration date
- name: domain expiry date
- name: domain creation date
- name: whois age
- name: domain research
- name: domain due diligence
- name: domain valuation
- name: expiration date lookup
- name: new domain detection
- name: domain history
x402Version: 2
x-payment-accepts:
- scheme: exact
  network: eip155:8453
  payTo: '0xE9740820225B3918b4ddd1292C7cA4Ca0e2C2F08'
  asset: '0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913'
- scheme: exact
  network: solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp
  payTo: 8ugAWAXDB8V18kiUrGZTq1oMvU3C6Fxs8hfC6rvzQT3b
  asset: EPjFWdd5AufqSSqeM2qN1xzybapC8G4wEGGkZwyTDt1v