What Is an A Record
Learn what an A record is, how it points a domain to an IPv4 address, when to change it, and how to check A records safely.
Introduction
An A record is the most common DNS record for websites. It connects a name like example.com to the IPv4 address of your hosting server.
You will see A records on root domains, subdomains, and sometimes on mail hostnames. They do not control email routing — that is what MX records are for.
Quick answer
An A record maps a hostname to an IPv4 address. When someone visits your domain, DNS uses the A record to find the server IP that hosts the website. If the A record is wrong or missing, the site may not load or may point to old hosting.
What it means
A stands for Address. An A record tells DNS resolvers which IPv4 address should receive traffic for a hostname.
- Root domain A record points example.com to a server
- www may use its own A record or a CNAME instead
- Changing A records moves website traffic to a new server
- IPv6 addresses use AAAA records, not A records
- TTL controls how long resolvers cache the A record
Where you see this:
- Website hosting — pointing a domain to a web server IP
- Subdomains like app.example.com or api.example.com
- Some mail hostnames that need a direct IP (MX still controls mail routing)
- Hosting migrations when you move to a new server
example.com. 300 IN A 192.0.2.10
www.example.com. 300 IN A 192.0.2.10Why this matters
If the A record points to the wrong IP, visitors see the wrong website, a parking page, or an error. During migrations, forgetting to update the A record is one of the most common reasons a site stays on old hosting.
How to check it
Confirm the live A record before and after DNS changes.
- Run DNS Lookup on your domain and note the IPv4 address returned.
- Check both the root domain and www if you use it.
- Compare the result with your hosting provider’s expected server IP.
- Use dig +short example.com A for a quick command-line check.
- If the site looks wrong, verify you edited DNS at the authoritative provider.
Look up A records
Use DNS Lookup to see which IPv4 address a domain or subdomain currently resolves to.
Common mistakes
A record still points to old hosting IP
HighThe domain resolves but loads a previous host or parking page.
Next step: Update the A record at authoritative DNS and wait for TTL to expire.
Root and www point to different servers
MediumVisitors get inconsistent results depending on whether they type www.
Next step: Point both to the same destination or redirect one to the canonical host.
AAAA still points to old server after migration
MediumIPv6 users may still reach the old host even when A was updated.
Next step: Update or remove the AAAA record if IPv6 is not in use.
DNS edited at the wrong provider
HighChanges were made where the zone is not authoritative.
Next step: Check NS records and edit DNS where nameservers point.
MX changed instead of A for a website move
MediumWebsite traffic and email routing were confused during migration.
Next step: Update A (and AAAA) for the website; change MX only for mail.
Example
example.com. 300 IN A 192.0.2.10
www.example.com. 300 IN A 192.0.2.10Frequently asked questions
What is the difference between A and AAAA records?
A records point to IPv4 addresses. AAAA records point to IPv6 addresses. Many domains use A only, both, or AAAA only depending on hosting support.
Can a domain have multiple A records?
Yes. Multiple A records can be used for redundancy or load balancing, but unintended extra A records can send some visitors to the wrong server.
Does an A record affect email delivery?
Not directly. Incoming email uses MX records. However, mail server hostnames often need A or AAAA records so MX targets can resolve.
How long does an A record change take?
Authoritative DNS may update quickly, but cached values remain until the previous TTL expires.
Should www use an A record or CNAME?
Both work. CNAME is common for www; A is common when you want both names on the same IP explicitly.
Related tools
Use these free tools to verify your configuration after applying changes.
Related guides
Browse all Glossary guides →Need help applying this fix?
Send us your domain, report link or issue details. CheckDomainHealth will review the request and route it to the right technical team if hands-on support is needed.
Was this guide helpful?
Your feedback helps us improve our guides for everyone.
Thanks for your feedback!