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Reverse DNS (PTR) Lookup

Reverse DNS (PTR) Lookup

Resolve IPv4 and IPv6 addresses to their hostnames using client-side DNS-over-HTTPS (DoH).

Query Settings

Enter an IP address and select a DoH resolver

Privacy Notice & Client-side Execution

Queries are fetched directly from your browser to public encrypted DNS-over-HTTPS (DoH) endpoints. Target IP queries are neither stored nor tracked on our servers.

    Examples

    Google Public DNS PTR

    Input
    IP: 8.8.8.8
    Output
    8.8.8.8.in-addr.arpa PTR dns.google.

    Resolves Google's 8.8.8.8 IPv4 address back to dns.google.

    About this tool

    The Reverse DNS (PTR) Lookup tool converts an IPv4 or IPv6 address into its PTR domain record via DNS-over-HTTPS. It automatically converts standard IP formats to in-addr.arpa or ip6.arpa domain notations and queries public encrypted DNS endpoints (Cloudflare, Google, Quad9) directly from your browser.

    How to use

    1. Enter IP address

      Type an IPv4 (e.g. 8.8.8.8) or IPv6 address (e.g. 2001:4860:4860::8888).

    2. Select DoH resolver

      Choose Cloudflare, Google, or Quad9 encrypted DNS-over-HTTPS resolver.

    3. Run PTR lookup

      Click Lookup or hit Enter to resolve the hostname associated with the IP.

    Use cases

    Email deliverability audit

    Verify that your mail server IP address has a matching valid reverse DNS (PTR) record to prevent spam filtering.

    Server log analysis

    Identify hostnames behind IP addresses appearing in server access or security firewall logs.

    Common mistakes

    Mistake:Assuming every IP has a PTR record.

    Fix:PTR records are optional and configured by the IP owner or hosting provider. Residential or unconfigured server IPs will return No Records Found.

    Frequently asked questions

    Related guides

    What Is Reverse DNS (PTR) and How Does It Work?

    Understand PTR records, reverse DNS zones, and common uses for IPv4 and IPv6 address lookups.

    References & standards

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