---
title: "Public one-try subdomain demo (no API key)"
method: GET
path: "/v1/demo/subdomains"
tags: ["demo", "demo"]
---

# Public one-try subdomain demo (no API key)

`GET /v1/demo/subdomains`

## Request

- Base URL: `https://api.ctindex.io`
- URL: `https://api.ctindex.io/v1/demo/subdomains`
- Auth: none declared

## Query parameters

- `domain` string, required: Registrable domain, e.g. stripe.com
- `limit` integer, nullable: Max subdomains to return (1–10). Omitted uses the demo cap. Non-integer values are HTTP 422, never ignored (GH #641).

## Response `200`

Successful Response

- DemoSubdomainResponse
  - `domain` string, required
  - `total_subdomains` integer, required
  - `total_is_lower_bound` boolean, required
  - `coverage` object, nullable
  - `results` DemoSubdomainEntry[], required
    - `subdomain` string, required
    - `first_seen` string, date-time, nullable
    - `last_seen` string, date-time, nullable
    - `cert_count` integer, required
  - `result_limit` integer, required
  - `latency_ms` integer, required
  - `cached` boolean, required
  - `docs_url` string
  - `signup_url` string

## Other responses

- `422`: Validation Error

---

[API](https://skmtc.dev/ctindex/apis/certindex-api.md) · [All operations](https://skmtc.dev/ctindex/apis/certindex-api/llms.txt) · [OpenAPI document](https://skmtc.dev/ctindex/apis/certindex-api/revisions/d5bc0ec85bc9?raw)