What it returns
Find the subdomains of any domain from public Certificate Transparency logs. Every publicly trusted SSL certificate is logged, so the hostnames on them map out a company's sites, apps, staging servers and services. Passive: nothing is sent to the target domain.
Subdomain, certificate count, first-seen date, latest certificate expiry, issuing certificate authorities, whether the name resolves in DNS today and its IP addresses.
Common uses
Attack-surface mapping and security reviews of your own domains, bug-bounty reconnaissance within programme scope, finding a company's products and tools for sales research, brand and phishing monitoring, and domain due diligence. Pay per subdomain.
Request
POST https://api.pushbuild.com/subdomain-finder/run with a JSON body. Send your key in the X-API-Key header.
| Field | Type | Description |
|---|---|---|
domains required | list of strings | Root domains to search, one per line (up to 20). |
resolve | boolean | Check which subdomains resolve today and return their IPs. Default: true. |
onlyResolving | boolean | Drop subdomains with no DNS record today. Default: false. |
includeWildcards | boolean | Return *.name entries as their own rows. Default: false. |
maxItems | integer | Maximum items to return (1-500). Default: 100. |
Example
curl -X POST https://api.pushbuild.com/subdomain-finder/run \
-H "X-API-Key: YOUR_KEY" \
-H "Content-Type: application/json" \
-d '{"domains": ["example.com"], "maxItems": 20}'Response
{"count": 20, "truncated": false, "seconds": 1.4, "items": [ { ... } ]}Each call returns up to 500 items. Records that fail validation or are not found are flagged in the items and not charged.
Pricing
Pay only for results returned: $0.24 per 1,000 subdomains. No charge for errors or empty searches.
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