> For the complete documentation index, see [llms.txt](https://help.rechat.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://help.rechat.com/guides/marketing/email-deliverability/how-email-authentication-works-spf-dkim-dmarc.md).

# How Email Authentication Works (SPF, DKIM, DMARC)

### **Simple Explanation**

When you send an email, providers want to confirm:“Is this sender legitimate?”Authentication proves your emails are truly coming from your domain.

### **What This Includes**

* **SPF**: Defines which servers are allowed to send emails for your domain
* **DKIM**: Verifies the email hasn’t been altered
* **DMARC**: Tells providers how to handle suspicious emails

### **Why This Matters**

Without authentication:

* Emails are more likely to go to spam
* Some messages may be blocked entirely

With proper setup:

* Your emails appear more trustworthy
* Inbox placement improves

### **Advanced Details**

When Rechat sends emails on your behalf, it must align with your domain.This is called **DKIM alignment**.To achieve this, Rechat is authorized to send using a subdomain of your domain, improving trust with providers like Gmail and Outlook.

{% content-ref url="/pages/Pk4cvAnkMIjdH0lcBXZa" %}
[DNS Self-Service Setup](/appendix/brokerage-set-up/email-delivery/dns-self-service-setup.md)
{% endcontent-ref %}


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