DNS Lookup Tool

What is DNS and why does it matter?

DNS (Domain Name System) is the distributed global directory that maps human-readable domain names to the numerical IP addresses computers use to communicate. Without DNS, reaching a website would require memorising raw IP addresses like 142.250.185.46 instead of simply typing google.com. The system is hierarchical: root servers delegate to top-level domain servers (.com, .org, .net), which delegate to the authoritative nameservers that hold the actual records for each domain.

Every internet activity — loading a page, sending email, joining a video call — begins with at least one DNS query. Speed and accuracy of DNS resolution directly affects how fast services feel to end users. Once you have an IP address from a DNS lookup, you can investigate it further using our IP Lookup tool for full geolocation and ISP details.

What does this DNS lookup tool actually do?

This tool queries the authoritative DNS servers for whatever domain you enter and retrieves all publicly available record types in real time: A, AAAA, MX, CNAME, NS, TXT and SOA. Results are never cached on our side — every lookup reflects the current live state of the domain's DNS configuration. Resolved IP addresses in the summary strip are clickable and link directly to our IP Lookup for instant geolocation and network details. You can copy all records to your clipboard with a single click for use in documentation or troubleshooting reports.

What do the different DNS record types mean?

Each record type has a specific, distinct function in the DNS system:

• A Record — Maps a hostname to an IPv4 address (e.g. 93.184.216.34). The most fundamental record type — it tells browsers and mail servers where to connect. Multiple A records provide basic load distribution.
• AAAA Record — The IPv6 counterpart of an A record. Domains with both A and AAAA records support dual-stack access, allowing IPv6 clients to bypass IPv4 entirely.
• MX Record — Specifies the mail servers responsible for accepting email for the domain. Priority numbers determine which server is tried first — lower numbers have higher priority. Multiple MX records provide mail delivery redundancy.
• CNAME Record — Creates an alias from one hostname to another. Useful for pointing subdomains to CDN or SaaS hostnames without managing IP addresses directly. Cannot coexist with other record types at the same name.
• NS Record — Identifies the authoritative nameservers for the domain. Changing NS records transfers DNS control from one provider to another (e.g. from your registrar to Cloudflare).
• TXT Record — Free-form text entries used for SPF (email sender authorisation), DKIM (cryptographic email signing), DMARC (email authentication policy), and domain ownership verification by Google, Cloudflare, and others.
• SOA Record — The Start of Authority record contains administrative metadata for the DNS zone: primary nameserver, contact email, serial number, and timing parameters that govern caching and zone transfers.

What is TTL and why does it matter for DNS changes?

TTL (Time To Live) is the number of seconds DNS resolvers and browsers are allowed to cache a record before re-querying the authoritative nameserver. A TTL of 300 means 5 minutes; 86400 means 24 hours. High TTLs reduce DNS query load and improve performance for end users. Low TTLs allow record changes to propagate more quickly after an update.

If you are planning a server migration or DNS cut-over, lower your TTL to 300 seconds at least 24–48 hours before the change. This ensures old cached records expire quickly worldwide after you update the records. Once the new server is confirmed working, raise the TTL back to a normal value. After switching servers, verify the HTTPS certificate on the new host with our SSL Checker.

What is DNS propagation and why does it take time?

DNS propagation is the process by which a record change spreads from the authoritative nameserver through the global network of recursive resolvers and caches. When you update an A record, resolvers around the world continue serving the cached old record until their TTL expires. The commonly cited "up to 48 hours" represents worst-case scenarios involving high TTLs or non-standards-compliant resolvers — in practice, most changes propagate within minutes when TTLs are set appropriately.

This tool always queries the authoritative nameservers directly, so results here reflect the latest published records even before propagation completes elsewhere. To confirm overall domain health alongside DNS, run a WHOIS Lookup to verify the domain registration has not lapsed or been transferred.

How do MX records affect email delivery?

When a mail server sends email to user@example.com, it looks up the MX records for example.com to find the destination mail server. Multiple MX records with different priority values provide redundancy: if the highest-priority server (lowest number) is unreachable, the sender tries the next. Google Workspace uses aspmx.l.google.com; Microsoft 365 uses [tenant].mail.protection.outlook.com.

If email delivery is failing, checking MX records here is the right first diagnostic step. Then use our Port Checker to confirm the mail server is reachable on port 25 or 587, and our SSL Checker to verify the certificate is valid for encrypted SMTP connections.

What are TXT records used for in practice?

TXT records are among the most versatile in DNS. Their most common uses are:

• SPF — Lists IP addresses and sending services authorised to send email on behalf of the domain. Missing or misconfigured SPF is a leading cause of legitimate email being rejected or sent to spam.
• DKIM — Publishes the public key used to verify cryptographic signatures on outbound email, allowing receiving servers to confirm the message has not been tampered with.
• DMARC — Declares the policy for handling email that fails SPF or DKIM checks: monitor, quarantine (send to spam), or reject outright.
• Domain verification — Services like Google Search Console, Cloudflare, Facebook, and Atlassian use TXT records to confirm you control a domain before granting access.

If legitimate email is landing in spam, inspecting TXT records here for SPF and DKIM is the right starting point. After confirming the records, check the sending server with our SSL Checker and verify connectivity with our Port Checker.

What is the difference between forward and reverse DNS?

A forward DNS lookup (what this tool performs) resolves a domain name into IP addresses and other associated records. A reverse DNS lookup goes the other direction: it takes an IP address and returns the hostname assigned to it via a PTR record. Reverse DNS is managed by the organisation that controls the IP block, not the domain owner, and is used by mail servers to verify sending IPs, by sysadmins to identify unknown hosts in logs, and by security tools to correlate IPs with hostnames. Use our dedicated Reverse DNS tool to look up the PTR record for any IP address.

When should I use a CNAME vs an A record?

Use an A record when you know the exact IP address of your server and it is stable — for example, pointing your root domain (example.com) at your web server's IP. Use a CNAME when you want to alias a subdomain to another hostname, such as pointing www.example.com to a CDN or SaaS platform hostname. CNAMEs are more flexible because the underlying IP can change at the CDN's end without any DNS update on your part.

Important constraint: you cannot place a CNAME at the zone apex (the root domain) alongside other records. Most DNS providers offer a proprietary ALIAS or ANAME record type as a workaround for this use case. After setting up or changing a CNAME, verify the TLS certificate is working correctly on the target with our SSL Checker.

How can I check if DNS changes have propagated?

Run a fresh lookup here — since this tool queries authoritative nameservers directly, results reflect the latest published records immediately after you save a change in your DNS provider's control panel. If the result here shows the new record but your browser still resolves the old IP, the issue is with your local resolver's cache. You can flush it: on Windows run ipconfig /flushdns; on macOS run sudo dscacheutil -flushcache; on Linux restart the systemd-resolved service. For external IP connectivity checks after a change, our Ping Test and Port Checker confirm the new server is reachable.

Is this tool free, and are my queries logged?

Completely free, no query limits, no account required. Every result is fetched live when you submit. Your queries are not stored, not associated with any user profile, and not used for any purpose beyond displaying your results. For a comprehensive view of any domain alongside its DNS records, pair this tool with WHOIS Lookup to check registration status, expiry date, and registrar details.

Other Network Utilities on Convixy

DNS lookup is one of over a dozen free network tools available on Convixy:

• What Is My IP — Detect your public IP address and get full geolocation, ISP, and connection details instantly.
• WHOIS Lookup — Check domain registration, registrar, expiry date, and ownership information.
• SSL Checker — Verify any domain's TLS certificate is valid, trusted, and not expired.
• Port Checker — Test whether any TCP port on any IP or hostname is publicly reachable.
• Reverse DNS — Look up the PTR record (hostname) assigned to any IP address.
• ASN Lookup — Find the Autonomous System number, operator, and IP ranges for any network organisation.
• HTTP Headers — Inspect all HTTP response headers returned by any URL.
• Ping Test — Measure round-trip response time and connectivity to any host.
• IP Geolocation — Get detailed location and network data for any IP address.
• MAC Address Lookup — Identify the hardware manufacturer for any device by its MAC address.
• Subnet Calculator — Calculate network addresses, broadcast addresses, and usable host ranges for any CIDR block.