{"eid":"duckdns","name":"DuckDNS","domain":"duckdns.org","resolved_by":"domain","topics":["domains-dns"],"n_records":1,"best_vorder":1,"review":null,"aliases":["DuckDNS","duckdns.org"],"records":[{"rid":"domains-dns/duckdns","card":{"rid":"domains-dns/duckdns","eid":"duckdns","topic":"domains-dns","slug":"duckdns","provider":"DuckDNS","url":"https://www.duckdns.org/spec.jsp","domain":"duckdns.org","category":"free dynamic subdomain","tier":null,"verdict":"qualifies-with-caveat","vorder":1,"grp":"usable","confidence":"measured","binding":"per-object-cap","identity_kind":"email","identity_basis":"stated","needs_card":0,"needs_phone":0,"needs_id":0,"needs_institution":0,"country":null,"crypto":null,"interfaces":"rest","egress_metered":0,"per_object_bytes":null,"retention_days":null,"verified_at":"2026-10-22T03:05:00.000Z","verified_basis":"live","checked_on":"2026-10-23","stale_on":"2027-01-21","n_evidence":2,"usd_month":null,"usd_per_tb_month":null,"summary":"subdomains under duckdns.org with a token API, IPv4, IPv6 and TXT support","duplicate_of":null,"n_unknown":0},"record":{"topic":"domains-dns","slug":"duckdns","provider":"DuckDNS","url":"https://www.duckdns.org/spec.jsp","category":"free dynamic subdomain","free_tier":{"stated":"subdomains under duckdns.org with a token API, IPv4, IPv6 and TXT support","unit":"unlimited","source_url":"https://www.duckdns.org/spec.jsp","read_on":"2026-10-22","metered_on":"none"},"per_object_cap":{"stated":"the number of subdomains per account is about 5, a third-party figure; DuckDNS publishes no number","bytes":null},"retention":{"stated":"a record persists until updated or cleared with clear=true, provided the account is used","days":null,"source_url":"https://www.duckdns.org/spec.jsp"},"egress":{"terms":"no query cap published","metered":false,"free_allowance":null,"price_per_tb":null,"source_url":"https://www.duckdns.org/spec.jsp"},"interface":["rest"],"interface_detail":"a single HTTPS GET per update; the token is a query parameter","tooling":"curl, any DDNS client, a router's built-in DuckDNS provider","chaining":"a name for a home IP or a tunnel endpoint, and nothing else: no certificate automation and no proxying","limits":[{"kind":"per-object-cap","value":"about 5 subdomains, a third-party figure; DuckDNS publishes no number","source":"https://www.duckdns.org/spec.jsp"}],"binding":"per-object-cap","identity_cost":{"kind":"email","detail":"Google, GitHub or Reddit OAuth","country":null},"reliability_note":"a bad token returns HTTP 200 with the body KO, so a status-only check reports success on a failed update","confidence":"measured","confidence_note":"the update endpoint was called today with an empty token and answered 200 KO, which proves both the endpoint and the failure shape. The subdomain cap is third-party.","evidence":[{"url":"probe:https://www.duckdns.org/update?domains=example&token=&ip=","date":"2026-10-22","proved":"200 with a two-byte body 'KO'. A 200 is not success; the rejection is in the body"},{"url":"https://www.duckdns.org/spec.jsp","date":"2026-10-22","proved":"the update URL, IPv4 and IPv6 parameters, the TXT form, and clear=true to delete records; a TXT record applies to all sub-subdomains under the name"}],"verdict":"qualifies-with-caveat","verified_at":"2026-10-22T03:05:00.000Z","price_per_tb_month":null,"notes":"A DuckDNS name cannot be a Cloudflare zone, so it cannot carry a Tunnel, Email Routing or Universal SSL. It is a dynamic-DNS tool, not a name a service can live on."},"claims":[{"path":"$.free_tier.stated","kind":"free-quota","num":null,"unit":null,"per":null,"currency":null,"usd":null,"fx_date":null,"parse":"unparsed"},{"path":"$.limits[0].value","kind":"limit:per-object-cap","num":null,"unit":null,"per":null,"currency":null,"usd":null,"fx_date":null,"parse":"unparsed"}],"unknown":[],"history":[],"drift":[]}]}