Bulk WHOIS for domains, IPs, and ASNs in one request
Mix domains, IPs, and ASNs in one batch
Most WHOIS tools are built for a single target type. Run a domain and you get registration data. Run an IP and you get network allocation data. But real-world workflows rarely fit that pattern — an incident investigation might start with an IP, expand to the ASN it belongs to, and involve several domains registered by the same actor.
DNS Buddy's bulk WHOIS lookup accepts domains, IPv4 addresses, IPv6 addresses, and ASNs in the same list. No need to switch tools or run separate queries. Add your targets, submit once, and get structured results for each.
Results use RDAP — the structured successor to legacy WHOIS — where available, with fallback to traditional WHOIS for registrars that haven't migrated yet.
What bulk WHOIS returns
Registrar, registration and expiry dates, name servers, registrant contact (where not redacted by privacy services), and DNSSEC status.
Regional Internet Registry (RIR) assignment, organization name, address block, and country of allocation.
Autonomous System Number details including the organization that holds the ASN, the IP ranges announced, and the RIR that manages it.
Abuse contact information and technical contact details for IP addresses — useful for abuse reports and incident notifications.
Results use RDAP where supported, giving consistent field names instead of free-form text that varies by registrar.
Paste your list, get results. Nothing to install, nothing to sign up for.
When bulk WHOIS is the right tool
Incident response and IP triage
A spike of suspicious requests, a firewall alert, a list of IPs from your WAF logs. Paste the list into bulk WHOIS and identify which organization owns each IP range in seconds. Cluster IPs from the same ASN to understand whether you're seeing a coordinated source. Get abuse contact details for filing reports.
Pre-acquisition domain research
Buying a domain or evaluating a portfolio? Bulk WHOIS returns registration and expiry dates for every domain in your list at once. Spot domains nearing expiry, check registrar consistency across a portfolio, and verify that transfer locks are in place where expected.
Third-party due diligence
Integrating with a new vendor or API? Check when their domain was registered and when it expires. Very recently registered domains or those expiring soon are worth flagging in a security review. WHOIS data adds a quick sanity check to vendor assessments.
Domain portfolio expiry auditing
If you manage multiple domains — brands, products, regional TLDs — bulk WHOIS is a fast way to audit expiry dates across your entire portfolio. Run the list periodically to make sure nothing is about to lapse.
What this tool doesn't do
DNS Buddy shows current registration data only. For historical WHOIS records — useful for tracking ownership changes over time — you need a dedicated WHOIS history service.
Many registrars use WHOIS privacy services that replace registrant contact fields with proxy data. This is standard practice and affects all WHOIS tools — DNS Buddy returns whatever the registry exposes.
This tool is WHOIS only. For bulk DNS record lookups (A, MX, TXT, CNAME, etc.) across multiple domains, use Bulk DNS Lookup instead.
Frequently asked questions
What is bulk WHOIS lookup?
Bulk WHOIS runs WHOIS queries for multiple targets at once instead of one at a time. DNS Buddy accepts a mixed list of domain names, IP addresses, and ASN numbers and returns structured ownership and network data for each using RDAP.
What is RDAP and how is it different from WHOIS?
RDAP (Registration Data Access Protocol) is the structured successor to legacy WHOIS. Instead of unformatted text that varies by registrar, RDAP returns JSON with consistent field names — making results easier to read and cross-reference. DNS Buddy uses RDAP by default, falling back to legacy WHOIS where RDAP is not yet available.
Can I look up IP addresses and ASNs with bulk WHOIS?
Yes. Paste a mixed list — domain names, IPv4, IPv6, and ASNs together — and DNS Buddy handles each one. This is useful in incident investigations where you have a mix of target types from different data sources.
Is bulk WHOIS lookup free?
Yes. DNS Buddy's bulk WHOIS is free with no account required.
Run a bulk WHOIS lookup — free, no account needed
Paste your list of domains, IPs, or ASNs and get structured ownership data for each target in one request.
Need DNS records too? Bulk DNS Lookup checks A, MX, TXT, and other record types across your domain list.
Not sure what the fields mean? How to read WHOIS output explains every field — registrar data, status codes, IP allocation, and RDAP vs legacy WHOIS.
Running infrastructure at scale? DNS tools for DevOps covers bulk DNS, FCrDNS validation, and fleet auditing workflows.