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 19 Aug 2026

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 19 Aug 2026, 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

Parameter	Type	Required	Description
`<email-or-domain>`	path	Required	Full 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

JSON Formatter

Format, beautify and minify JSON online with 2-space, 4-space or tab indentation. Sort keys alphabetically and catch syntax errors instantly — free and private.

Alternatives to Kickbox Disposable API

If Kickbox Disposable does not fit, these security & auth apis cover similar ground. Every one was called before publishing, and each links to its own reference page with a working curl command and the response it returned.

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MITRE ATT&CK TAXII	Free MITRE ATT&CK TAXII 2.1 server with no key: fetch the Enterprise, Mobile and ICS knowledge bases as STIX 2.1 objects — techniques, tactics, groups, software and mitigations.	No key	No	21 Aug 2026
MDN HTTP Observatory	Free MDN HTTP Observatory API with no key: scan any site's security headers — CSP, HSTS, X-Frame-Options — and get a graded score with fixes. Tested.	No key	Yes	20 Aug 2026

All Security & Auth APIs

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