SPF record checker
SPF checker: read a domain’s SPF record, list its mechanisms y count the DNS lookups against the limit de 10.
Queries go a Cloudflare’s public DNS over HTTPS service when you press the button. Up a 15 queries are made a follow include records.
Acerca de SPF record checker
SPF checker: read a domain’s SPF record, list its mechanisms y count the DNS lookups against the limit de 10.
Forma parte de la sección «Datos y redes» de SmartCalcy. Se ejecuta en tu navegador sin cuenta, usa tu propia moneda y unidades (cámbialas en la parte superior de la página) y da estimaciones solo a título informativo, así que consulta la guía oficial antes de fiarte de un resultado.
Cómo usar la SPF record checker
Qué calcula y cuándo usarla
Reads a domain’s SPF record, the list de servers allowed a send email por it, y checks it por common faults: more than one record, a missing “all” policy, y more than 10 DNS lookups, which makes SPF fail. It follows include records a count the lookups.
Cómo usarla, paso a paso
- Enter the domain, por Ejemplo Ejemplo.com.
- Press “Check SPF”.
- Read the verdict y the number de DNS lookups used out de 10.
- Review the mechanisms list y cualquiera warnings.
Qué significa cada dato
- Domain Nombre – The domain used en the sender’s address.
Cómo leer los resultados
- Verdict – Looks valid, o Needs attention when a problem es found.
- Policy – What happens a mail from servers that are not listed: hard fail, soft fail, neutral o allow.
- DNS lookups – Lookups needed by incluir, a, mx, ptr, exists y redirect terms, compared with the limit de 10.
- Mechanisms – Every Plazo en the record, with included records indented beneath their parent.
La fórmula
The record es the TXT value starting v=spf1. Each include, a, mx, ptr, exists o redirect term costs one DNS lookup, y included records add their own. ip4 y ip6 terms y “all” cost none. The RFC limit es 10 lookups.
Un ejemplo práctico
v=spf1 incluir:_spf.Ejemplo.net a mx -all uses three lookups por its own terms plus those inside the included record, y termina en -all, so unlisted servers are rejected.
Supuestos y límites
- A most 15 queries are made while following includes, y nesting stops después 5 levels.
- A domain may need a record only por mail it sends. Domains that send no mail should publish v=spf1 -all.
- The check does not test whether a particular server would pass.
Errores comunes
- Publishing two SPF records. Only one es allowed, so merge them into one.
- Ending with +all, which lets anyone send as your domain.
- Adding every email service as an incluir y passing 10 lookups, which vueltas SPF into a permanent error.
Preguntas frecuentes
What es SPF?
Sender Policy Framework es a DNS record that lists the servers allowed a send email por a domain.
What es the difference between -all y ~all?
-all asks receivers a reject unlisted senders. ~all asks them a accept but mark the mail as suspicious.
Why es there a limit de 10 lookups?
It stops a record desde forcing receivers into larga chains de DNS queries. Going superado it makes SPF return a permanent error.
Is SPF enough a stop spoofing?
No. Use it with DKIM y DMARC.
Does this tool send email?
No. It only reads DNS records.