# DNS Info | Free Online DNS Lookup & Propagation Checker

> DNS Info (https://dnsinfo.live) is a high-performance, developer-grade online DNS resolution, propagation checking, and email deliverability diagnostic platform.

## Overview

DNS Info performs real-time, hop-by-hop root-to-authoritative DNS lookups across any valid domain name, hostname, or IP address. It traces nameserver delegations, records TTL, checks syntax against IETF RFC standards, and runs propagation tests across multiple global geographic regions.

## Key Capabilities & Tools

- [A Record Lookup](https://dnsinfo.live/A): Resolves IPv4 host addresses and verifies nameserver glue records.
- [AAAA Record Lookup](https://dnsinfo.live/AAAA): Resolves IPv6 addresses and checks modern dual-stack IPv4/IPv6 reachability.
- [MX Record Lookup](https://dnsinfo.live/MX): Resolves mail exchanger records, verifies priority weighting, and identifies primary mail routing hosts.
- [NS Record Lookup](https://dnsinfo.live/NS): Inspects authoritative nameservers delegated by top-level domains (TLDs).
- [CNAME Lookup](https://dnsinfo.live/CNAME): Resolves canonical alias chains and identifies redirect targets.
- [TXT Record Checker](https://dnsinfo.live/TXT): Lists all published text attributes, verification tokens, and security declarations.
- [SPF Analyzer & Validator](https://dnsinfo.live/SPF): Analyzes v=spf1 syntax, calculates DNS query lookup depth against the 10-lookup RFC 7208 limit, and identifies missing authorizations.
- [DKIM Record Checker](https://dnsinfo.live/DKIM): Validates domain DKIM public keys, key length, selector records, and cryptographic signatures.
- [DMARC Policy Checker](https://dnsinfo.live/DMARC): Validates _dmarc domain policies, alignment mechanisms, reporting endpoints, and enforcement percentage.
- [Email Blacklist Checker](https://dnsinfo.live/BLACKLIST): Scans 50+ DNSBL and RBL real-time spam databases to detect IP and domain reputation issues.
- [SSL Certificate Checker](https://dnsinfo.live/SSL): Inspects SSL/TLS certificates, expiry dates, issuer chains, SAN names, and protocol security.
- [Online Ping Tool (ICMP)](https://dnsinfo.live/PING): Measures round-trip time (RTT), latency, packet loss, and host reachability across IPv4/IPv6 networks.
- [Online Traceroute](https://dnsinfo.live/TRACEROUTE): Traces network router hops, hop latency, and packet loss path to any destination host or IP.
- [Open Port Checker](https://dnsinfo.live/PORT): Tests TCP port availability (open, closed, or filtered) on any remote host or IP address.
- [Open Relay Test](https://dnsinfo.live/RELAY): Tests mail servers (MX) for insecure SMTP open relay vulnerabilities to prevent spam abuse and blacklist flags.
- [SOA Record Inspector](https://dnsinfo.live/SOA): Queries zone authority serial numbers, primary nameserver, admin contact, and refresh/retry/expire timers.
- [PTR Reverse DNS Lookup](https://dnsinfo.live/PTR): Performs reverse DNS pointer lookups mapping IPv4/IPv6 addresses to verified hostnames.
- [CAA Record Checker](https://dnsinfo.live/CAA): Discovers authorized Certificate Authorities (CAs) permitted to issue SSL/TLS certificates.
- [SRV Record Finder](https://dnsinfo.live/SRV): Resolves service port, protocol, weight, and host targets.
- [HTTPS & SVCB Lookup](https://dnsinfo.live/HTTPS): Inspects HTTP/3 service binding and ALPN parameters under RFC 9460.
- [DNSSEC Chain of Trust](https://dnsinfo.live/DS): Validates Delegation Signer (DS) hashes and public zone signing keys.
- [Multi-Region Propagation Checker](https://dnsinfo.live/multi): Simultaneously queries distributed global resolvers across North America, Europe, Asia-Pacific, South America, and Africa to measure global record propagation.

## Technical Standards & RFC Compliance

- [RFC 1034 - Domain Concepts](https://datatracker.ietf.org/doc/html/rfc1034): Core domain system concepts and facilities.
- [RFC 1035 - DNS Implementation](https://datatracker.ietf.org/doc/html/rfc1035): Domain implementation and specification standard.
- [RFC 3596 - IPv6 DNS Extensions](https://datatracker.ietf.org/doc/html/rfc3596): DNS support for IP version 6 (AAAA records).
- [RFC 7208 - Sender Policy Framework](https://datatracker.ietf.org/doc/html/rfc7208): SPF for authorizing email senders.
- [RFC 7489 - DMARC](https://datatracker.ietf.org/doc/html/rfc7489): Domain-based Message Authentication, Reporting, and Conformance.
- [RFC 8659 - CAA Records](https://datatracker.ietf.org/doc/html/rfc8659): DNS Certification Authority Authorization.
- [RFC 9460 - Service Binding & HTTPS](https://datatracker.ietf.org/doc/html/rfc9460): Service binding and parameter advertisement.
- [RFC 4033 - DNSSEC Overview](https://datatracker.ietf.org/doc/html/rfc4033): DNS Security Introduction and Requirements.

## Optional

- [DNS Info Homepage](https://dnsinfo.live): Free online DNS lookup and monitoring service.
- [Contact & Support](https://dnsinfo.live/contact): Get in touch with our engineering and support team.
- [Privacy Policy](https://dnsinfo.live/privacy-policy): Privacy policy and data handling practices.