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Kickbox Disposable API

Free Kickbox open API with no key: check whether an email domain is disposable. Returns a single boolean, extremely fast and simple. Tested curl example.

No API key requiredHTTPSFree tier

Endpoint tested and returned HTTP 200 on 2026-08-19

What is the Kickbox Disposable API?

The Kickbox disposable email API is a free, open endpoint that returns whether a given email address or domain belongs to a disposable email provider. It requires no API key and returns a single boolean field.

This is about as minimal as a useful API gets: one request, one boolean. Kickbox publishes it as a free public service alongside their commercial email verification product, and it needs no signup.

Because the response is tiny and the check is cheap, it is well suited to running inline during signup validation. For deeper checks — mailbox existence, role addresses, catch-all detection — you would need their paid verification API.

Quick facts

Base URL
https://open.kickbox.com/v1/disposable
Authentication
No API key required for this open endpoint.
Rate limit
No published limit on the open endpoint.
Pricing
Free.
CORS
Not enabled — call it from your server
Official docs
Read the docs

How to use the Kickbox Disposable API

Every request below was executed against the live API on 2026-08-19, and the response shown is the real body it returned — not an illustration.

1. Check whether a domain is disposable

GET https://open.kickbox.com/v1/disposable/test@mailinator.com

curl
curl 'https://open.kickbox.com/v1/disposable/test@mailinator.com'
JavaScript (fetch)
const res = await fetch("https://open.kickbox.com/v1/disposable/test@mailinator.com");
if (!res.ok) throw new Error(`Request failed: ${res.status}`);
const data = await res.json();
console.log(data);
Python (requests)
import requests

res = requests.get("https://open.kickbox.com/v1/disposable/test@mailinator.com", timeout=20)
res.raise_for_status()
print(res.json())
Response — HTTP 200
{
  "disposable": true
}

Parameters

ParameterTypeRequiredDescription
<email-or-domain>pathRequiredFull address or bare domain to check. test@mailinator.com

Response fields

disposableboolean
True when the domain is a known disposable email provider.

What you can build with the Kickbox Disposable API

  • Inline signup validation with a single fast request
  • Reject throwaway addresses on free trial registration
  • Score lead quality in a CRM pipeline
  • Cross-check results from another disposable-email API

Common errors and how to fix them

404

Malformed path.

Fix: Pass the address or domain directly in the path with no query string.

Unknown new domains return false

The list cannot cover every newly registered throwaway service.

Fix: Combine with a second signal such as DNS/MX validation for stronger coverage.

Kickbox Disposable API — frequently asked questions

Is the Kickbox disposable API free?

Yes, it is an open endpoint requiring no API key or signup. Kickbox provides it free alongside their paid verification product.

What does it actually check?

Only whether the domain belongs to a known disposable email provider. It does not verify that the mailbox exists or that mail will be delivered.

How is it different from Disify?

Kickbox returns just a disposable boolean; Disify additionally reports format validity, DNS status and whether the domain is a whitelisted major provider. Using both gives a stronger signal.

Can I verify whether an inbox actually exists?

Not with this endpoint. Mailbox-level verification requires Kickbox's paid API, since it involves SMTP probing.

Tools that pair with this API

Kickbox Disposable is an independent third-party service and is not affiliated with ByteTools or ByteVancer. Details on this page were verified on 2026-08-19; always check the official documentation before relying on this API in production, as terms and limits can change.