Vacant

Describe the brand you want. Vacant suggests names with AI and shows only the domains you can actually register.

Vacant is a free, open-source, self-hostable domain finder. Clone it and run it, or pull the prebuilt container. Nothing is hosted for you and nothing is monetized.

Screenshots

Only-available results, checked live and ranked best first:

Patterns are highlighted as you type, so you can see the shape of the name:

Features

• Two ways to search: describe a brand in plain words, or sketch its shape with patterns.
• Only available names: every suggestion is checked against the registries before you see it.
• Ranked best first: results are scored for length, pronounceability, and brandability.
• Live price estimates: a keyless lookup adds a yearly price to each available name.
• Save and revisit: favorites and recent searches are kept locally in your browser.
• Self-hostable: one command with Bun, or one container. Bring your own API key.

How it works

Type in two ways, or mix them:

• Plain words: a calm fintech brand, short and warm. The AI proposes brandable names.
• Patterns: sketch the shape of the name.
  • (animals): a slot the AI fills in.
  • (com/io): exact options, no AI, no guessing.
  • Everything else is literal: get(action word)app.(com/io).

Every suggestion is ranked best-first, then checked for real registration availability. You only see names you can register, each with a live price estimate and a one-click link to a registrar.

Availability is resolved server-side through a cascade that is free and key-optional for most TLDs:

1. RDAP: the authoritative registry lookup (from the IANA bootstrap).
2. DNS: an existing A record proves a domain is taken.
3. WHOIS: a fallback for TLDs the first two miss.
4. Domainr: an optional final fallback if you supply a key.

Results stream back as each domain resolves, behind a shared cache and a concurrency limit, so a search of dozens of names is one request, not a storm.

Quick start

Requires Bun.

bun install
cp .env.example .env.local   # add your OpenRouter key
bun dev

Open http://localhost:3000.

Environment variables

Variable	Required	Purpose
OPENROUTER_API_KEY	Yes	Powers AI suggestions. Get one at https://openrouter.ai/keys.
OPENROUTER_MODEL	No	Any OpenRouter model with structured output. Default google/gemini-3.5-flash.
DOMAINR_RAPIDAPI_KEY	No	Improves availability accuracy on TLDs that RDAP and WHOIS miss.

Pricing comes from a public, keyless endpoint, so no extra key is needed for the price estimates.

Pick a fast instruction-tuned model. Heavy reasoning models are slower, cost more, and can fail to return the structured output Vacant needs.

Run with Docker

Pull and run the published image:

docker run -p 3000:3000 -e OPENROUTER_API_KEY=sk-... ghcr.io/martian56/vacant:latest

Or with Compose, using a local .env:

docker compose up

Build the image yourself:

docker build -t vacant .
docker run -p 3000:3000 -e OPENROUTER_API_KEY=sk-... vacant

Development

bun run dev          # start the dev server
bun run build        # production build (standalone output)
bun run test         # run the unit tests
bun run lint         # eslint
bun run typecheck    # tsc --noEmit
bun run format       # prettier --write
bun run update-tlds  # refresh lib/tlds.json from the IANA RDAP bootstrap

Stack

Bun · Next.js (App Router) · TypeScript · Tailwind CSS · Vercel AI SDK · OpenRouter.

Contributing

Issues and pull requests are welcome. Please read CONTRIBUTING.md and the Code of Conduct first.

License

MIT