What is a DKIM record?

A DKIM record is a DNS TXT entry containing your domain’s public key. It verifies that an email’s content hasn’t been altered and that it comes from an authorized source.

How do I check my DKIM record?

Enter your domain and selector in MailTested’s DKIM Checker to instantly fetch and validate your DKIM public key.

What causes DKIM validation failures?

Failures happen when the DKIM record is missing, the selector is incorrect, or the public key doesn’t match your mail server’s private key.

How can I fix DKIM issues?

Publish the correct DKIM TXT record for your selector in DNS, confirm proper formatting, and retest using MailTested to ensure your record resolves correctly.

检查您域名的 DKIM 记录

即时验证您的 DKIM 记录。检查您的选择器、公钥和 DNS 配置。

🚀 第一步：输入您的域名和选择器

探索更多工具: SPF Checker • SPF Generator • DMARC Checker • IP Blacklist Checker

Learn more: What is DKIM? • Fix DKIM Errors • Improve Email Deliverability

📘 DKIM Checker — Frequently Asked Questions

A DKIM record is a DNS TXT entry containing a public key used to verify that an email message was not altered during transmission. It’s critical for email authenticity and domain reputation.

It queries your DNS for the DKIM TXT record based on the provided domain and selector, validates the syntax, and reports errors or missing keys so you can correct them easily.

A selector helps mail servers locate the DKIM public key in DNS. For example, in default._domainkey.example.com, “default” is the selector name.

A typical DKIM record might look like:
v=DKIM1; k=rsa; p=MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQ...
This tells receiving servers which public key to use for signature verification.

📨 Why DKIM Validation Matters

DKIM ensures that your emails are not modified after being sent. Without a valid DKIM record, your messages risk being flagged as spam or rejected by receiving servers. MailTested’s DKIM Checker instantly validates your selector and public key to confirm your setup is secure.

Combine DKIM with SPF and DMARC for full authentication alignment, improving deliverability across Gmail, Outlook, and Yahoo Mail.

🔧 Why Use MailTested’s DKIM Checker

MailTested provides real-time DKIM lookup and validation. It detects missing records, mismatched selectors, or truncated public keys — common causes of DKIM failures. It’s built for both developers and deliverability specialists who need quick diagnostics.

For technical reference, see the official DKIM RFC 6376 specification.