Check how old a list of domains is and when they expire
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.
https://domain-age-checker.underscoredone.com/lookup$0.01 per request — pay via x402/USDC. No account needed.
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.
| Name | Type | Required | Description |
|---|---|---|---|
domains | array | yes | 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. |
{
"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"
}| Status | Meaning |
|---|---|
400 | Bad request — your input failed validation or could not be processed. Check the detail field for specifics. |
402 | Payment required. Send a signed USDC payment on Base Mainnet or Solana Mainnet using the x402 protocol. |
422 | Unprocessable — a required field is missing or the wrong type. Check the detail field for specifics. |