SPF
An email authentication technology that declares a list of IP addresses authorized to send mail for a domain via DNS TXT records. It is used to prevent email spoofing and phishing attacks by enabling receiving mail servers to verify the sender's identity.
Core Facts
Professional email sending practices include using mailbox warm-up tools to build domain reputation, configuring SPF/DKIM/DMARC domain authentication records, and controlling daily sending volume and sending intervals.
SPF declares authorized IPs via DNS TXT records, DKIM adds a digital signature to email headers via asymmetric encryption to verify that content has not been tampered with, and DMARC defines handling policies for authentication failures and provides aggregate reports.
SPF、DKIM、DMARC三项技术配置是企业邮件基础设施的必选项，用于保证邮件送达性
Timeline (last 90 days)
The author built an email deliverability check API that in one call returns SPF/DKIM/DMARC/MX/rDNS verdicts for a domain, along with remediation tips.
The three protocols SPF, DKIM, and DMARC are all bound to the sending domain, not to the Gmail account itself.
Configuring SPF alone without DKIM will still cause many large email service providers to lower their trust score for the email.
Configuring a dedicated domain for each AI Agent is extremely costly, requiring individual setup of DNS, SPF, DKIM, and DMARC along with a lengthy IP warm-up process.
Properly configuring a domain's SPF, DKIM, and DMARC records is the basic line of defense for reducing the risk of algorithmic misclassification
Gmail and Google Workspace have built a reputation scoring system that comprehensively evaluates multiple dimensions including a domain's SPF, DKIM, and DMARC configuration, sending volume, bounce rate, and user complaint rate
Certain forwarding scenarios can cause SPF validation failures, or specific DMARC policy combinations may resemble known email service provider patterns, thereby triggering algorithmic classification rules
传统反垃圾邮件技术栈依赖 SPF、DKIM、DMARC 等验证机制以及贝叶斯过滤器等算法进行事后过滤
SPF declares authorized IPs via DNS TXT records, DKIM adds a digital signature to email headers via asymmetric encryption to verify that content has not been tampered with, and DMARC defines handling policies for authentication failures and provides aggregate reports.
All Facts (13)
Professional email sending practices include using mailbox warm-up tools to build domain reputation, configuring SPF/DKIM/DMARC domain authentication records, and controlling daily sending volume and sending intervals.
75%VerifiedSPF declares authorized IPs via DNS TXT records, DKIM adds a digital signature to email headers via asymmetric encryption to verify that content has not been tampered with, and DMARC defines handling policies for authentication failures and provides aggregate reports.
70%VerifiedSPF、DKIM、DMARC三项技术配置是企业邮件基础设施的必选项，用于保证邮件送达性
65%VerifiedDMARC is an email authentication protocol built on top of SPF and DKIM that allows domain owners to tell receiving parties how to handle emails that fail authentication.
65%VerifiedSPF通过DNS TXT记录声明哪些IP地址被授权代表某域名发送邮件
65%UnverifiedThe three protocols SPF, DKIM, and DMARC are all bound to the sending domain, not to the Gmail account itself.
50%UnverifiedConfiguring SPF alone without DKIM will still cause many large email service providers to lower their trust score for the email.
50%UnverifiedConfiguring a dedicated domain for each AI Agent is extremely costly, requiring individual setup of DNS, SPF, DKIM, and DMARC along with a lengthy IP warm-up process.
50%UnverifiedGmail and Google Workspace have built a reputation scoring system that comprehensively evaluates multiple dimensions including a domain's SPF, DKIM, and DMARC configuration, sending volume, bounce rate, and user complaint rate
50%UnverifiedCertain forwarding scenarios can cause SPF validation failures, or specific DMARC policy combinations may resemble known email service provider patterns, thereby triggering algorithmic classification rules
50%UnverifiedProperly configuring a domain's SPF, DKIM, and DMARC records is the basic line of defense for reducing the risk of algorithmic misclassification
50%Unverified传统反垃圾邮件技术栈依赖 SPF、DKIM、DMARC 等验证机制以及贝叶斯过滤器等算法进行事后过滤
50%UnverifiedThe author built an email deliverability check API that in one call returns SPF/DKIM/DMARC/MX/rDNS verdicts for a domain, along with remediation tips.
50%