API Reference

Domain Availability & Search API

Check domain availability and pricing programmatically — one name at a time or up to 50 per request — across thousands of TLDs, including extensions most registrars don't support.

Generate an API key View the full API docs

Validating availability across many names and extensions — for brand-protection sweeps, defensive registration planning, or a customer-facing search box — is slow and error-prone when it's done by hand. The 101domain API turns it into endpoints: one for a single domain, one for bulk lookups of up to 50 at a time. Both return availability, pricing, and terms in a single call.

Checking a single domain

Use GET /v1/domains/search to check one domain. The response includes whether the name is available, its pricing, and available registration terms.

GET /v1/domains/search?domain=example.com
Authorization: Bearer YOUR_API_KEY

A successful response returns availability and pricing for the requested name:

{
    "domain": "example.com",
    "available": false,
    "currency": "USD",
    "pricing": {
        "registration": 19.99,
        "renewal": 21.99,
        "term_years": 1
    }
}

Aftermarket domains are not currently supported in search results.

Bulk availability checks (up to 50 at once)

For portfolio-scale work, POST /v1/domains/bulk-search checks up to 50 names in a single request — efficient for brand-protection monitoring, defensive registration planning, and customer-facing bulk search tools.

POST /v1/domains/bulk-search
Authorization: Bearer YOUR_API_KEY
Content-Type: application/json

{
    "domains": ["example.com", "example.net", "example.io"]
}

Each name is returned with its availability and pricing, ready to feed a dashboard or report.

TLD breadth and pricing data

Availability is only useful if it covers the extensions your brand actually needs. The API reaches the same broad TLD catalog 101domain is known for — including ccTLDs and specialty extensions that most registrars don't carry. Pair search with the TLD endpoints to pull registration requirements, pricing, and terms for any extension before you commit.

  • Thousands of TLDs, including ccTLDs with local presence requirements.
  • Full pricing data — registration and renewal — returned with results.
  • Registration requirements surfaced per TLD via the TLD lookup endpoints.
Explore the full API Endpoints Reference →

Getting started

  1. Generate an API key. Domain search and availability are read operations that work with any API key — no specific scope is required.
  2. Reference the API documentation for the full request and response schema.
  3. Programmatic registration and renewal are coming soon — see the Registration & Renewal API.

Add domain search to your application

Generate a key and start checking availability today, or talk to us about high-volume use.

Generate an API key Talk to our team