100% Free — No Credit Card

Free API — 1,000 Monthly Requests for WHOIS, DNS & More

One free API key unlocks WHOIS lookups, DNS records, and domain availability checks. 1,000 requests per month with native JSON responses — no hidden costs, no credit card, no time limit.

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All-In-One Access

One API Key, All Services

Your free plan isn't limited to WHOIS. A single token unlocks our entire suite of domain intelligence tools.

Whois Lookup

Full ownership and registration data — registrar, dates, nameservers, and status codes in structured JSON.

DNS Records

A, AAAA, MX, TXT, CNAME, and more. Resolve any record type for any domain in a single API call.

Domain Availability

Real-time registration status checks. Instantly know if a domain is available or already taken.

SSL Certificates

Verify SSL validity, issuer details, and expiration dates for any domain — all through the same token.

No need for multiple keys. Use your free token to access our entire suite of domain tools — WHOIS, DNS, availability, and SSL — all included in your 1,000 monthly requests.

What You Get for Free

A Truly Free API — No Strings Attached

Lightning Fast

Average response time under 200ms. Our free tier runs on the same infrastructure as premium — no throttling, no slow lane.

Free Forever

Your free plan never expires. Get 1,000 API requests every month, automatically renewed — no credit card required to sign up.

Native JSON Output

Clean, well-parsed JSON responses ready for immediate use. No messy text parsing required — works with any programming language.

Comparison

WhoisJson vs Standard Competitors

See why thousands of developers choose WhoisJson for their domain data needs.

Criteria	WhoisJson	Standard Competitors
Free Requests / Month	1,000	100 or less
Response Speed	< 200ms	500ms – 2s
Credit Card Required	No	Often Yes
Native JSON Format
RDAP Support
Comprehensive Documentation		Varies

How to Integrate Our Free API into Your Project

Send a Simple HTTP Request

Our free API allows developers to automate domain ownership checks, DNS resolution, and availability monitoring in Python, Node.js, and PHP — without parsing messy text. Simply send an HTTP request with the target domain and receive a clean, structured JSON object containing registration dates, registrar details, nameservers, and expiry information. No SDK to install — any language that supports HTTP can query the free WhoisJson API in a single line of code.

Get Normalized, Consistent Data

Unlike legacy WHOIS tools that return raw, unformatted text, WhoisJson normalizes data from hundreds of registrars and RDAP servers into a consistent schema. With a single free API key, you can build domain monitoring dashboards, brand-protection bots, or cybersecurity scanners without writing custom parsers for every TLD. The free tier includes 1,000 requests per month across all endpoints — WHOIS, DNS, availability, and SSL — enough to power prototypes, side projects, and low-volume production apps at zero cost.

Scale When You're Ready

Getting started is free and takes less than a minute: create your free account, copy your API key from the dashboard, and pass it in the Authorization header. Check our full API documentation for advanced options like XML output, force-refresh, and domain availability endpoints. When your project outgrows the free plan, premium plans start at $10/month with up to 30,000 requests and priority support.

Tip: Your free token works on every endpoint — WHOIS, DNS, SSL, and availability. No need to create separate accounts or manage multiple keys.

Quick Start

Up and Running in 30 Seconds

One simple HTTP request is all it takes. Copy the curl command below and try it now.

Request

cURL

curl -s "https://whoisjson.com/api/v1/whois?domain=example.com" \
  -H "Authorization: TOKEN=YOUR_API_KEY"

Response

JSON

{
  "domain": "example.com",
  "registered": true,
  "created": "1995-08-14T00:00:00Z",
  "updated": "2024-08-14T07:01:44Z",
  "expires": "2025-08-13T04:00:00Z",
  "registrar": "RESERVED-Internet Assigned Numbers Authority",
  "nameservers": [
    "a.iana-servers.net",
    "b.iana-servers.net"
  ],
  "status": [
    "clientDeleteProhibited",
    "clientTransferProhibited",
    "clientUpdateProhibited"
  ]
}

FAQ

Frequently Asked Questions

What are the limits of the free plan?

The free plan gives you 1,000 API requests per month with a rate limit of 20 requests per minute. You get full access to WHOIS, DNS, and SSL certificate data in JSON format. This is ideal for personal projects, prototyping, and low-volume applications.

Do I need a credit card to sign up?

Absolutely not. Create your account and receive your API key instantly — no payment information required. You can start making API calls within seconds of signing up.

How can I get a free API key?

Getting your free API key takes less than 30 seconds. Sign up for a free account with just your email address — no credit card, no phone number. Your API key appears instantly on your dashboard. Copy it, paste it into your Authorization header, and you're ready to make your first free WHOIS query.

How do I upgrade to a premium plan?

When your project grows, upgrading is seamless. Visit our pricing page to compare plans, then upgrade directly from your dashboard. Your new limits apply immediately, with no downtime or key changes.

Get Your Free API Key Now

Join thousands of developers who use our free API for WHOIS, DNS, and domain availability data. Sign up in seconds — your free API key is one click away.

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