General Domain Setup

Setting up a custom sending domain improves deliverability and allows you to send from your own email addresses. This guide covers the general process that works with any DNS provider.

Using a specific provider? We have dedicated guides for Cloudflare, Vercel, Namecheap, Porkbun, and more.

Why Use a Custom Domain?

Better deliverability: Email providers trust authenticated domains
Brand consistency: Send from [email protected] instead of a shared domain
Full control: Manage your sender reputation independently

Prerequisites

Access to your domain’s DNS settings (usually through your registrar or hosting provider)
An Ark account with API access

Step 1: Add Your Domain

Dashboard
Python
Node.js
cURL

Go to Domains in your Ark dashboard
Click Add Domain
Enter your domain name (e.g., mail.yourdomain.com)
Copy the DNS records shown

from ark import Ark

client = Ark()

domain = client.domains.create(name="mail.yourdomain.com")

print(f"Domain ID: {domain.data.id}")
print(f"DNS Zone: {domain.data.dns_records.zone}")
print("DNS Records to configure:")

spf = domain.data.dns_records.spf
print(f"  SPF: {spf.type} {spf.name} -> {spf.value}")

dkim = domain.data.dns_records.dkim
print(f"  DKIM: {dkim.type} {dkim.name} -> {dkim.value}")

rp = domain.data.dns_records.return_path
print(f"  Return Path: {rp.type} {rp.name} -> {rp.value}")

import Ark from 'ark';

const client = new Ark();

const domain = await client.domains.create({
  name: 'mail.yourdomain.com',
});

console.log(`Domain ID: ${domain.data.id}`);
console.log(`DNS Zone: ${domain.data.dnsRecords.zone}`);
console.log('DNS Records to configure:');

const { spf, dkim, returnPath } = domain.data.dnsRecords;
console.log(`  SPF: ${spf.type} ${spf.name} -> ${spf.value}`);
console.log(`  DKIM: ${dkim.type} ${dkim.name} -> ${dkim.value}`);
console.log(`  Return Path: ${returnPath.type} ${returnPath.name} -> ${returnPath.value}`);

curl -X POST https://api.arkhq.io/v1/domains \
  -H "Authorization: Bearer $ARK_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"name": "mail.yourdomain.com"}'

The API response includes the DNS records you need to add:

{
  "data": {
    "id": "dom_abc123",
    "name": "mail.yourdomain.com",
    "verified": false,
    "dnsRecords": {
      "zone": "yourdomain.com",
      "spf": {
        "type": "TXT",
        "name": "mail",
        "fullName": "mail.yourdomain.com",
        "value": "v=spf1 a mx include:spf.arkhq.io ~all",
        "status": null
      },
      "dkim": {
        "type": "TXT",
        "name": "ark-abc123._domainkey.mail",
        "fullName": "ark-abc123._domainkey.mail.yourdomain.com",
        "value": "k=rsa;t=s;p=MIGfMA0GCSqGSIb3DQEB...",
        "status": null
      },
      "returnPath": {
        "type": "CNAME",
        "name": "psrp.mail",
        "fullName": "psrp.mail.yourdomain.com",
        "value": "rp.arkhq.io",
        "status": null
      }
    }
  }
}

Understanding the response:

zone - The DNS zone where you’ll add records (your root domain)
name - The relative hostname to enter in your DNS provider (most providers auto-append the zone)
fullName - The complete FQDN for reference
value - The record value to copy

For a root domain like yourdomain.com, the SPF name would be @ (representing the apex).

Step 2: Configure DNS Records

Add the following records to your DNS provider. Most providers auto-append your domain name, so use the name field (not fullName).

SPF Record

SPF tells receiving servers which IPs are authorized to send email for your domain.

Field	Value
Type	`TXT`
Name	Use the `name` from the API (e.g., `mail` for subdomains, `@` for root)
Value	`v=spf1 a mx include:spf.arkhq.io ~all`
TTL	3600 (or Auto/Default)

Already have an SPF record? Edit your existing record instead of creating a new one. Add include:spf.arkhq.io to your existing record. Only one SPF record is allowed per domain.Example: v=spf1 include:spf.arkhq.io include:_spf.google.com ~all

DKIM Record

DKIM cryptographically signs your emails to prove they came from your domain.

Field	Value
Type	`TXT`
Name	Use the `name` from the API (e.g., `ark-abc123._domainkey.mail`)
Value	The DKIM value from the API response (starts with `k=rsa;t=s;p=...`)
TTL	3600 (or Auto/Default)

Return Path (CNAME)

The return path handles bounce messages and improves deliverability.

Field	Value
Type	`CNAME`
Name	Use the `name` from the API (e.g., `psrp.mail`)
Value	`rp.arkhq.io`
TTL	3600 (or Auto/Default)

Step 3: Verify Your Domain

After adding DNS records, wait for propagation (usually a few minutes, can take up to 48 hours) and verify:

Dashboard
Python
Node.js
cURL

Go to Domains and click Verify DNS records on your domain.

result = client.domains.verify("dom_abc123")

if result.data.verified:
    print("Domain verified successfully!")
else:
    print("DNS records not found. Check your configuration.")
    # Check individual record statuses
    records = result.data.dns_records
    print(f"  SPF: {records.spf.status}")
    print(f"  DKIM: {records.dkim.status}")
    print(f"  Return Path: {records.return_path.status}")

const result = await client.domains.verify('dom_abc123');

if (result.data.verified) {
  console.log('Domain verified successfully!');
} else {
  console.log('DNS records not found. Check your configuration.');
  // Check individual record statuses
  const { spf, dkim, returnPath } = result.data.dnsRecords;
  console.log(`  SPF: ${spf.status}`);
  console.log(`  DKIM: ${dkim.status}`);
  console.log(`  Return Path: ${returnPath.status}`);
}

curl -X POST https://api.arkhq.io/v1/domains/dom_abc123/verify \
  -H "Authorization: Bearer $ARK_API_KEY"

Success! Once all three records show status OK, you can send emails from any address at your domain (e.g., [email protected], [email protected]).

Optional: DMARC Configuration

DMARC adds another layer of authentication and tells receiving servers how to handle emails that fail authentication. Add this TXT record:

Field	Value
Type	`TXT`
Name	`_dmarc.mail` (or `_dmarc` for root domain)
Value	`v=DMARC1; p=none; rua=mailto:[email protected]`

Start with p=none to monitor, then move to p=quarantine or p=reject once you’re confident in your configuration.

Troubleshooting

Verification failing

Check DNS propagation: Use dnschecker.org to verify records are visible globally
Check record values: Ensure you copied the exact values from the API response
Check record names: Use the name field, not fullName - most DNS providers auto-append your domain
Wait and retry: DNS can take up to 48 hours to propagate fully

SPF issues

You can only have one SPF record per domain
If you have multiple email services, combine them: v=spf1 include:spf.arkhq.io include:_spf.google.com ~all
SPF has a 10 DNS lookup limit. Use SPF checker tools to verify

Subdomain vs root domain

For subdomains like mail.yourdomain.com:

SPF name: mail (not @)
DKIM name: ark-xyz._domainkey.mail
Return Path name: psrp.mail

For root domains like yourdomain.com:

SPF name: @
DKIM name: ark-xyz._domainkey
Return Path name: psrp

Next Steps

Send Your First Email

Test your new domain with a real email

Provider-Specific Guides

Step-by-step instructions for your DNS provider

Overview

DNS Setup Guides

Why Use a Custom Domain?

Prerequisites

Step 1: Add Your Domain

Step 2: Configure DNS Records

SPF Record

DKIM Record

Return Path (CNAME)

Step 3: Verify Your Domain

Optional: DMARC Configuration

Troubleshooting

Next Steps

Send Your First Email

Provider-Specific Guides

Overview

DNS Setup Guides

​Why Use a Custom Domain?

​Prerequisites

​Step 1: Add Your Domain

​Step 2: Configure DNS Records

​SPF Record

​DKIM Record

​Return Path (CNAME)

​Step 3: Verify Your Domain

​Optional: DMARC Configuration

​Troubleshooting

​Next Steps

Send Your First Email

Provider-Specific Guides

Why Use a Custom Domain?

Prerequisites

Step 1: Add Your Domain

Step 2: Configure DNS Records

SPF Record

DKIM Record

Return Path (CNAME)

Step 3: Verify Your Domain

Optional: DMARC Configuration

Troubleshooting

Next Steps