Deliverability & Authentication

How to Set Up DKIM, SPF, and DMARC

Email authentication is essential for deliverability. SPF, DKIM, and DMARC records prove your domain owns the emails you send. Without them, ISPs are more likely to reject or mark your messages as spam.

Time: 20 min
Level: Intermediate
dkim spf dmarc email authentication

What you'll need

Before you start, make sure you have the following ready.

  • Access to your domain DNS settings
  • An OutSends account with a verified sending domain
  • Basic DNS configuration knowledge

Step-by-step guide

Follow these steps to complete the setup.

Log into your DNS provider

Go to your domain registrar or hosting provider where you manage DNS records (Cloudflare, GoDaddy, Namecheap, etc.).

Add SPF record

Add a TXT record: v=spf1 include:_spf.outsends.com ~all. This authorizes OutSends to send on your behalf.

Add DKIM record

Add a TXT record for the DKIM selector provided by OutSends. The value is a long public key string.

Add DMARC record

Add a TXT record for _dmarc.yourdomain.com. Start with p=none to monitor, then move to p=quarantine or p=reject.

Verify in OutSends

Go to Settings > Authentication. Enter your domain and click Verify. OutSends checks all three records.

Tips for best results

Pro tips to get the most out of this setup.

  • Start DMARC with p=none until you confirm emails pass SPF and DKIM
  • DMARC reports help you spot unauthorized use of your domain
  • Re-verify after any DNS change — propagation can take 24-48 hours

Frequently asked questions

What if I already have SPF records?

You can only have one SPF record. Use includes to add OutSends: include:_spf.outsends.com alongside your existing entries.

Do I need all three records?

SPF and DKIM are the minimum. DMARC is highly recommended and required by Gmail and Yahoo for bulk senders.

Will strict DMARC (p=reject) block my normal emails?

No, if your normal emails pass SPF or DKIM, they are authenticated. DMARC only blocks unauthenticated messages.

Related guides

Explore more how-to guides for OutSends.

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