What are domains?
A domain is the foundation of your sending identity in SendKit. Before you can send any email, you need to add and verify at least one domain. This proves you own the domain and authorizes SendKit to send on your behalf. For example, if you want to send emails fromhello@acme.com, you need to add and verify acme.com.
Adding a domain
Select a region
Choose the region closest to your recipients for best performance. This cannot be changed after creation.
Configure DNS records
SendKit generates 4 DNS records you need to add at your DNS provider. See DNS records below.
DNS records
When you add a domain, SendKit generates 4 DNS records. You need to add these at your DNS provider (Cloudflare, AWS Route 53, GoDaddy, etc.).DKIM (required)
DKIM cryptographically signs your emails so recipients can verify they haven’t been tampered with.| Field | Value |
|---|---|
| Type | TXT |
| Name | sendkit._domainkey.yourdomain.com |
| Value | v=DKIM1; k=rsa; p=<your-public-key> |
| TTL | 3600 |
The DKIM public key is unique to your domain and generated automatically by SendKit. Copy the full value from the domain detail page.
SPF (required)
SPF tells receiving mail servers that SendKit is authorized to send emails for your domain.| Field | Value |
|---|---|
| Type | TXT |
| Name | send.yourdomain.com |
| Value | Shown on your domain detail page |
| TTL | 3600 |
MX (required)
The MX record on thesend subdomain enables bounce and complaint handling.
| Field | Value |
|---|---|
| Type | MX |
| Name | send.yourdomain.com |
| Value | Shown on your domain detail page |
| Priority | 10 |
| TTL | 3600 |
The exact MX value depends on the region you selected. Copy it from your domain detail page.
DMARC (optional)
DMARC builds on top of DKIM and SPF to define how receiving servers should handle unauthenticated emails.| Field | Value |
|---|---|
| Type | TXT |
| Name | _dmarc.yourdomain.com |
| Value | v=DMARC1; p=none; |
| TTL | 3600 |
DMARC is not required for verification, but we strongly recommend adding it. It protects your domain from spoofing and improves deliverability.
Verification
After you add the DNS records at your provider, come back to the domain detail page and click Refresh. SendKit checks both your DNS records and the email identity status.Statuses
| Status | Meaning |
|---|---|
| Not started | Domain was just added, no verification attempted yet |
| Pending | Verification in progress — DNS records detected but still propagating |
| Verified | All required records confirmed. You can send emails |
| Partially verified | Some records verified, but not all required ones |
| Failed | Required records not found or incorrect |
| Temporary failure | A transient issue occurred during verification. Will be retried automatically |
Automatic checks
You don’t need to keep clicking Refresh. SendKit automatically checks pending domains:- First 2 hours — every 10 minutes
- 2–12 hours — every 30 minutes
- 12–72 hours — every 60 minutes
Domain configuration
Once added, you can configure tracking and security settings from the Configuration tab:Click tracking
When enabled, links in your HTML emails are rewritten to pass through SendKit before redirecting to the original URL. This lets you track which recipients clicked which links.Open tracking
When enabled, a 1x1 transparent pixel is inserted into each email to detect when it’s opened.TLS mode
| Mode | Behavior |
|---|---|
| Opportunistic (default) | Attempts TLS encryption, falls back to unencrypted if the recipient’s server doesn’t support it |
| Enforced | Requires TLS. If the recipient’s server doesn’t support TLS, the email is rejected |
Domains and senders
Domains and senders work together:- A domain must be verified before you can create senders on it
- Each sender uses an email address on a verified domain (e.g.,
hello@acme.com) - If a domain loses verification, all senders on that domain are disabled until re-verified
Domain warmup
New domains go through an automatic warmup period to build sender reputation. During warmup, daily sending volume is gradually increased over 14 days.Deleting a domain
A domain can only be deleted if it has no senders. Remove all senders first, then delete the domain from the dropdown menu on the domain detail page. When a domain is deleted:- The domain and its DNS records are removed from SendKit
- All associated infrastructure is cleaned up automatically
- You can remove the DNS records from your provider
Deleting a domain does not affect emails that were already sent.
FAQ
How many domains can I add?
How many domains can I add?
The number of domains depends on your plan. Check your plan details for the domain limit.
Can I use a subdomain?
Can I use a subdomain?
Yes. You can add
mail.acme.com or any subdomain. The DNS records will be generated for that subdomain.How long does DNS propagation take?
How long does DNS propagation take?
Most DNS providers propagate changes within minutes. In rare cases, it can take up to 24-48 hours depending on your provider and TTL settings.
Do I need to add all 4 DNS records?
Do I need to add all 4 DNS records?
DKIM, SPF, and MX are required for verification. DMARC is optional but strongly recommended for better deliverability and domain protection.
What region should I choose?
What region should I choose?
Choose the region closest to the majority of your recipients. This reduces latency and can improve delivery speed. The region cannot be changed after domain creation.
Can two teams use the same domain?
Can two teams use the same domain?
No. Each domain is unique per team. However, different teams can use different subdomains of the same root domain.