What is a DNS record?

A DNS record is an entry in a DNS zone file that maps a hostname to a value. Different record types serve different purposes: A maps a name to an IPv4 address, MX specifies mail servers, TXT holds arbitrary text (used for SPF, DKIM, and domain verification).

What is TTL and what value should I use?

TTL (Time To Live) controls how long resolvers cache the record, in seconds. Lower TTL (300–3600) is useful before planned changes — resolvers invalidate faster. Higher TTL (86400 = 1 day) reduces DNS query load once records are stable.

What is the difference between an A and AAAA record?

An A record maps a hostname to an IPv4 address (32-bit, e.g. 203.0.113.1). An AAAA record maps to an IPv6 address (128-bit, e.g. 2001:db8::1). Both are needed if your server supports dual-stack.

What is the MX priority number?

MX priority (preference) determines the order mail servers are tried. Lower numbers have higher priority. Use 10 for the primary server, 20 for a backup. If two records have the same priority, servers are tried in random order (load balancing).

What is a TXT record used for?

TXT records hold arbitrary text data. Common uses: SPF (authorise mail senders), DKIM (cryptographic email signing), DMARC (mail policy), domain ownership verification (Google, Let's Encrypt), and BIMI (brand logo in email).

What is a CAA record?

A CAA (Certification Authority Authorization) record specifies which Certificate Authorities are allowed to issue certificates for your domain. For example: 0 issue "letsencrypt.org" restricts issuance to Let's Encrypt only. CAs check CAA before issuing.

What is an SRV record and when do I need one?

An SRV (Service) record maps a service name and protocol to a host and port. It is used by SIP, XMPP, Minecraft, and other protocols. Format: _service._proto.name TTL IN SRV priority weight port target.

How long does a DNS change take to propagate?

Changes propagate as existing cached records expire (up to their TTL). With a TTL of 3600, you may wait up to 1 hour for global propagation. Lower the TTL 48 hours before a planned change to speed up propagation.

DNS Record Builder

Select a record type, fill in the fields, and get the zone file line and dig verification command. Runs entirely in your browser.

100% client-side · no upload

Record type

Name / Host

TTL (seconds)

Value

Zone file record

Verification command

How to use the DNS Record Builder

Select the record type from the dropdown.
Fill in the name/host and any record-specific fields.
Copy the zone file record and paste it into your DNS provider's interface or zone file.
After saving, run the verification dig command to confirm propagation.

常見問題

What is a DNS record?: A DNS record is an entry in a DNS zone file that maps a hostname to a value. Different record types serve different purposes: A maps a name to an IPv4 address, MX specifies mail servers, TXT holds arbitrary text (used for SPF, DKIM, and domain verification).
What is TTL and what value should I use?: TTL (Time To Live) controls how long resolvers cache the record, in seconds. Lower TTL (300–3600) is useful before planned changes — resolvers invalidate faster. Higher TTL (86400 = 1 day) reduces DNS query load once records are stable.
What is the difference between an A and AAAA record?: An A record maps a hostname to an IPv4 address (32-bit, e.g. 203.0.113.1). An AAAA record maps to an IPv6 address (128-bit, e.g. 2001:db8::1). Both are needed if your server supports dual-stack.
What is the MX priority number?: MX priority (preference) determines the order mail servers are tried. Lower numbers have higher priority. Use 10 for the primary server, 20 for a backup. If two records have the same priority, servers are tried in random order (load balancing).
What is a TXT record used for?: TXT records hold arbitrary text data. Common uses: SPF (authorise mail senders), DKIM (cryptographic email signing), DMARC (mail policy), domain ownership verification (Google, Let's Encrypt), and BIMI (brand logo in email).
What is a CAA record?: A CAA (Certification Authority Authorization) record specifies which Certificate Authorities are allowed to issue certificates for your domain. For example: 0 issue "letsencrypt.org" restricts issuance to Let's Encrypt only. CAs check CAA before issuing.
What is an SRV record and when do I need one?: An SRV (Service) record maps a service name and protocol to a host and port. It is used by SIP, XMPP, Minecraft, and other protocols. Format: _service._proto.name TTL IN SRV priority weight port target.
How long does a DNS change take to propagate?: Changes propagate as existing cached records expire (up to their TTL). With a TTL of 3600, you may wait up to 1 hour for global propagation. Lower the TTL 48 hours before a planned change to speed up propagation.

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