DNS Record Lookup
Look up DNS records including A, AAAA, MX, NS, SOA, CNAME, TXT, and CAA records for any domain
Hosting & Network
once.com runs on Cloudflare, with DNS by Cloudflare and email configured.
- Hosting network
- CloudflareAS13335Cloudflare
- Managed DNS
- Cloudflare
- Configured
- IPv6 (AAAA)
- Not enabled
- CAA pinning
- Set
Sits alongside 4,999+ other sites on Cloudflare. Stable here since we started watching (Aug 31, 2026).
The apex and www are the same hosting — the apex via A records.
DNS Records for once.com
| Hostname | Type | TTL | Priority | Content |
|---|---|---|---|---|
| once.com | MX | 0 | 10 | app-mx.37signals.com |
| once.com | TXT | 0 | gw91nsyn47zz1m9zvnlzjtj9ws001z3w | |
| once.com | TXT | 0 | v=spf1 include:_spf.basecamp.com -all | |
| once.com | SOA | 60 | merlin.ns.cloudflare.com dns.cloudflare.com 2411419072 10000 2400 604800 60 | |
| once.com | NS | 0 | merlin.ns.cloudflare.com | |
| once.com | NS | 0 | serena.ns.cloudflare.com | |
| once.com | A | 0 | 104.18.0.101 | |
| once.com | A | 0 | 104.18.1.101 | |
| once.com | CAA | 0 | 0 issuewild pki.goog; cansignhttpexchanges=yes | |
| once.com | CAA | 0 | 0 issuewild comodoca.com | |
| once.com | CAA | 0 | 0 issue ssl.com | |
| once.com | CAA | 0 | 0 issue pki.goog; cansignhttpexchanges=yes | |
| once.com | CAA | 0 | 0 issuewild digicert.com; cansignhttpexchanges=yes | |
| once.com | CAA | 0 | 0 issue digicert.com; cansignhttpexchanges=yes | |
| once.com | CAA | 0 | 0 issuewild ssl.com | |
| once.com | CAA | 0 | 0 issue globalsign.com | |
| once.com | CAA | 0 | 0 issue amazon.com | |
| once.com | CAA | 0 | 0 issue comodoca.com | |
| once.com | CAA | 0 | 0 issuewild letsencrypt.org | |
| once.com | CAA | 0 | 0 iodef mailto:sysadmins@37signals.com | |
| once.com | CAA | 0 | 0 issue letsencrypt.org | |
| www.once.com | A | 0 | 104.18.1.101 | |
| www.once.com | A | 0 | 104.18.0.101 |
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About DNS Records
DNS (Domain Name System) records are instructions that provide information about a domain, including its IP addresses, mail servers, and other services. Common record types include:
- SOA (Start of Authority) - Contains administrative information about the zone
- NS (Nameserver) - Specifies authoritative nameservers for the domain
- A (Address) - Maps a domain to an IPv4 address
- AAAA - Maps a domain to an IPv6 address
- CNAME (Canonical Name) - Creates an alias pointing to another domain
- MX (Mail Exchange) - Specifies mail servers for the domain