One-click custom domains for SaaS. Automatic DNS, domain verification, and SSL/TLS on your users' own domains.

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CustomDomain™ lets a platform's users connect a domain they already own in one click. It detects the user's DNS provider, writes the records automatically, verifies them against public DNS, and issues and renews TLS certificates at a managed edge. 63 DNS and registrar providers are catalogued: 25 configure automatically (17 by scoped API token, 6 by provider OAuth, 2 by Domain Connect), and the other 38 use a guided manual flow with automatic verification. A domain connected through provider authorization is typically live with HTTPS in about 30 seconds.

The connect flow, run on a real domain: provider detected, records written and verified, certificate issued.

Your user types their domain

Live with HTTPS, seconds later

Also: e-commerce platforms (a storefront per merchant domain), creator tools (a domain per creator), and any multi-tenant SaaS where tenants deserve their own name in the address bar. Start at custom domains for SaaS.

One connect flow across the entire provider landscape: one-click authorization where providers support it, API tokens where they offer them, and a guided manual path with automatic verification everywhere else. No user ever hits a dead end.

claude mcp add --transport http customdomain https://mcp.customdomain.ai/mcp \
  --header "Authorization: Bearer $CUSTOMDOMAIN_API_KEY"

{
  "mcpServers": {
    "customdomain": {
      "type": "http",
      "url": "https://mcp.customdomain.ai/mcp",
      "headers": { "Authorization": "Bearer sk_live_YOUR_KEY" }
    }
  }
}

# 1. Create a connection for your user's domain (the application comes from the key)
curl -X POST https://api.customdomain.ai/v1/connections \
  -H "Authorization: Bearer $API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"domain": "app.customer.com"}'

# 2. Start one-click provider authorization (fallbacks: token or guided manual).
#    return_origin is required and must be on your allowlist.
curl -X POST https://api.customdomain.ai/v1/connections/<ID>/oauth:start \
  -H "Authorization: Bearer $API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"return_origin": "https://app.yourplatform.com"}'

# 3. Poll until live: records written, verified in public DNS, TLS issued
curl https://api.customdomain.ai/v1/connections/<ID> \
  -H "Authorization: Bearer $API_KEY"

How do I let my users connect their own domain? Embed the connect widget or call the REST API. CustomDomain™ handles provider detection, DNS, verification, certificates, and serving.

What is bring your own domain (BYOD)? Letting each customer run your product on a domain they own, like app.acme.com, instead of a shared subdomain. Full definition, and custom domain vs subdomain if you're weighing the tradeoffs.

How fast can a customer domain go live? With one-click provider authorization, about 30 seconds from typing the domain to serving HTTPS. Guided manual setups depend on the customer applying records; verification is detected automatically once they do.

Does this work for email domains? Yes. SPF, DKIM, DMARC, MX, and return-path records are written through the same connect flow. See connect-domain-for-email-platforms.

Is there a free tier? Yes. The Free plan is $0 for 10 domain connections a year and includes the Connect DNS engine, the widget and SDK, the REST API and webhooks, DNS drift detection, and the MCP server. The reverse-proxy edge and the SSL management API start on the Growth plan. See pricing.

custom-domain-checks (v0.1.1) is a GitHub App that watches the custom domain on your GitHub Pages repositories and posts a Domain health check on every push: DNS resolution, CNAME or apex target correctness, domain verification (takeover protection), CAA compatibility, certificate expiry, and HTTPS enforcement. It opens a tracking issue the moment something breaks. The service is deployed, but the public App is not registered on GitHub yet, so it cannot be installed from GitHub today; the source is open and free to run yourself.

Connect your first domain free →

_{Docs: docs.customdomain.ai · Questions: Discussions · Status: status.customdomain.ai · Account and billing: connect@customdomain.ai · Security: security@customdomain.ai (policy) · Security posture and sub-processors: trust.customdomain.ai · Book a call}

_{CustomDomain™ is a product of EverJust Company.}