Answers/What is a custom subdomain?

What is a custom subdomain?

Updated March 2026

A custom subdomain gives you a branded URL like alice.sutrena.com instead of sutrena.com/p/slug. It is available on all plans, including Free.

Set it with PUT /api/account/subdomain. The subdomain must be 3 to 30 characters, lowercase alphanumeric with hyphens, and cannot start or end with a hyphen. Reserved names like www, api, app, admin, and cdn are blocked.

Once set, your pages are served at your subdomain. If you have a page with slug "about", it lives at alice.sutrena.com/about. The slug "index" becomes the root: alice.sutrena.com/ serves it as the homepage.

Read your current subdomain with GET /api/account/subdomain. Change it anytime with another PUT. The old subdomain stops working immediately.

Subdomains are unique across all Sutrena users. First come, first served. If "alice" is taken, try "alice-dev" or something else.

This works well for personal sites, portfolios, project documentation, and landing pages. You get a clean, memorable URL without buying a domain or configuring DNS. Deploy pages via the API, and they are live at your subdomain instantly.

For a fully custom domain (yourdomain.com instead of alice.sutrena.com), see custom domains. That requires Builder ($9/month) or above, plus a CNAME record pointing to cname.sutrena.com.

# Set your subdomain
curl -X PUT https://sutrena.com/api/account/subdomain \
  -H "Authorization: Bearer st_live_your_key" \
  -H "Content-Type: application/json" \
  -d '{ "subdomain": "alice" }'

# Response:
# { "subdomain": "alice", "url": "https://alice.sutrena.com" }

# Check your current subdomain
curl https://sutrena.com/api/account/subdomain \
  -H "Authorization: Bearer st_live_your_key"

# Deploy a page — it is now at alice.sutrena.com/hello
curl -X POST https://sutrena.com/api/pages \
  -H "Authorization: Bearer st_live_your_key" \
  -H "Content-Type: application/json" \
  -d '{
    "slug": "hello",
    "title": "Hello World",
    "html": "<h1>Welcome to my site</h1>"
  }'

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What is a custom subdomain? — Sutrena | Sutrena