# Agent Margin Router, free: Domain WHOIS API

> Domain registration data via RDAP (the WHOIS successor): registered flag, registrar, status, registration/expiry events, nameservers and DNSSEC – for availability checks and due diligence.

Agent Margin Router's Free plan for the domain WHOIS API costs $0.00 per 1,000 domains. We check each provider's docs for 9 fields. Agent Margin Router's docs list 4: Registrar, Name servers, Statuses, DNSSEC.
We haven't run Agent Margin Router through [our domain WHOIS API benchmark](https://datacircle.dev/best-domain-whois-api.txt) yet.
This plan is free. We rank 631 plans for domain WHOIS APIs by price. Half the plans cost $1.663 or less per 1,000 domains. [128 domain WHOIS API plans on our price sheet are free.](https://datacircle.dev/best-domain-whois-api.txt) [WhoisRequest's free plan](https://datacircle.dev/domain-whois-apis/whoisrequest/free-get-api-v1-lookup-whois-domain-name/llms.txt) scores highest of the free plans in our benchmark, at 96.9 out of 100.
[Searchwire's $10 pack](https://datacircle.dev/domain-whois-apis/searchwire/10-pack/llms.txt) is the cheapest paid plan per 1,000 domains. Searchwire's domain WHOIS API costs nothing beyond the plan price. [UAPI's CNY 4.90 pack](https://datacircle.dev/domain-whois-apis/uapi/cny-4-90-pack/llms.txt) costs the least for 10,000 domains a month: about $0.73.
[WhoisRequest](https://datacircle.dev/domain-whois-apis/whoisrequest/free-get-api-v1-lookup-whois-domain-name/llms.txt), [thenetworkery](https://datacircle.dev/domain-whois-apis/thenetworkery/free/llms.txt) and [FluentEDI](https://datacircle.dev/domain-whois-apis/fluentedi/free/llms.txt) are the best domain WHOIS API providers in the Datacircle benchmark.

- This page: https://datacircle.dev/domain-whois-apis/agent-margin-router/free
- [Domain WHOIS API in 2026: the best of 40+ providers compared](https://datacircle.dev/best-domain-whois-api.txt)
- Get it: https://agentmarginrouter.com/pricing?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=domain-whois-api-pricing
- Request: `POST https://agent-margin-router-production.up.railway.app/domain-rdap`
- API key: not needed
- Its API docs: https://agent-margin-router-production.up.railway.app/docs?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=domain-whois-api-pricing#/opendata/domain_rdap_domain_rdap_post
- Sold by: Agent Margin Router (https://agentmarginrouter.com?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=domain-whois-api-pricing)
- Checked: 2026-11-11

## In the answer

- Completeness: 44%
- Registrar: ✓
- Name servers: ✓
- Statuses: ✓
- DNSSEC: ✓

## Price

- $ per 1,000 domains: $0.00
- Per: call
- Billing: free

## Charges

- Also pays for: from the same budget: 49 other Agent Margin Router calls

## Overage

- $ per 1,000 domains: $10.00
- Units cap: soft

## Not found

- $ per 1,000 calls that find nothing: $0.00

## In their words

- Their pitch: Domain registration data via RDAP (the WHOIS successor): registered flag, registrar, status, registration/expiry events, nameservers and DNSSEC – for availability checks and due diligence.

## Data

- Keep data: no API terms
- Use data: no API terms

## Plan

- Pay: $0
- You get: 3 requests
- Enough for: 3 calls

## Rate limit

- Batch: 1

## Speed

- Answer: in the call

## The call

- You send: domain. Optional: max_age_seconds
- Method: POST
- Path: /domain-rdap

## About the plan

- Plan: Free
- Who can get it: anyone

## The 13 fields the plan's answer can hold

domain, registered, registrar, registrar IANA ID, registered at, expires at, updated at, statuses, nameservers, DNSSEC signed, RDAP URL, fetched at, cache hit

## Agent Margin Router's plans (9)

- [Agent Margin Router, free](https://datacircle.dev/domain-whois-apis/agent-margin-router/free/llms.txt): $0.00 per 1,000, 44% complete
- [Agent Margin Router, pay as you go](https://datacircle.dev/domain-whois-apis/agent-margin-router/pay-as-you-go/llms.txt): $10.00 per 1,000, 44% complete
- [Agent Margin Router, top-up from $5](https://datacircle.dev/domain-whois-apis/agent-margin-router/top-up-from-5/llms.txt): $10.00 per 1,000, 44% complete
- [Agent Margin Router, $9 monthly](https://datacircle.dev/domain-whois-apis/agent-margin-router/9-monthly/llms.txt): $0.18 per 1,000, 44% complete
- [Agent Margin Router, $49 monthly](https://datacircle.dev/domain-whois-apis/agent-margin-router/49-monthly/llms.txt): $0.098 per 1,000, 44% complete
- [Agent Margin Router, $199 monthly](https://datacircle.dev/domain-whois-apis/agent-margin-router/199-monthly/llms.txt): no limit, 44% complete
- [Agent Margin Router, $84 yearly](https://datacircle.dev/domain-whois-apis/agent-margin-router/84-yearly/llms.txt): $0.14 per 1,000, 44% complete
- [Agent Margin Router, $468 yearly](https://datacircle.dev/domain-whois-apis/agent-margin-router/468-yearly/llms.txt): $0.078 per 1,000, 44% complete
- [Agent Margin Router, $1,908 yearly](https://datacircle.dev/domain-whois-apis/agent-margin-router/1908-yearly/llms.txt): no limit, 44% complete

## Agent Margin Router's calls for this API (1)

- `POST /domain-rdap`: [Agent Margin Router, free](https://datacircle.dev/domain-whois-apis/agent-margin-router/free/llms.txt)

## Agent Margin Router's APIs (6)

- [Agent Margin Router Domain WHOIS API pricing, 9 plans](https://datacircle.dev/domain-whois-apis/agent-margin-router/free/llms.txt)
- [Agent Margin Router Email verification API pricing, 9 plans](https://datacircle.dev/validate-email-apis/agent-margin-router/free/llms.txt)
- [Agent Margin Router IP company lookup API pricing, 9 plans](https://datacircle.dev/ip-company-lookup-apis/agent-margin-router/free/llms.txt)
- [Agent Margin Router Web scraping API pricing, 9 plans](https://datacircle.dev/web-scraping-apis/agent-margin-router/free/llms.txt)
- [Agent Margin Router SERP API pricing, 9 plans](https://datacircle.dev/serp-apis/agent-margin-router/free/llms.txt)
- [Agent Margin Router GitHub repository API pricing, 9 plans](https://datacircle.dev/github-repository-apis/agent-margin-router/free/llms.txt)

## Agent Margin Router: domain WHOIS API alternatives

[Agent Margin Router alternatives: other domain WHOIS API providers by price](https://datacircle.dev/agent-margin-router-alternatives.txt)

We list Agent Margin Router's cheapest paid plan first. Next we list other providers' plans closest to Agent Margin Router in price per 1,000 domains.

- [Agent Margin Router, $468 yearly](https://datacircle.dev/domain-whois-apis/agent-margin-router/468-yearly/llms.txt): $0.078 per 1,000, 44% complete
- [UAPI, CNY 24.90 pack](https://datacircle.dev/domain-whois-apis/uapi/cny-24-90-pack/llms.txt): $0.074 per 1,000, 78% complete
- [Wapi, CNY 1,068 yearly](https://datacircle.dev/domain-whois-apis/wapi/cny-1068-yearly/llms.txt): $0.087 per 1,000, 78% complete
- [Enterno, ₽4,116 yearly](https://datacircle.dev/domain-whois-apis/enterno/4116-yearly/llms.txt): $0.09 per 1,000, 89% complete, live
- [TidyTools, $14.99 monthly](https://datacircle.dev/domain-whois-apis/tidytools/14-99-monthly/llms.txt): $0.10 per 1,000, 89% complete

## Sources

From each provider's own pricing page and docs, and from what providers tell us. We read this row from these pages on 2026-11-11.

- https://agent-margin-router-production.up.railway.app/docs?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=domain-whois-api-pricing
- https://agent-margin-router-production.up.railway.app/openapi.json?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=domain-whois-api-pricing
- https://agentmarginrouter.com/?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=domain-whois-api-pricing
- https://agentmarginrouter.com/prepaid?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=domain-whois-api-pricing
- https://agentmarginrouter.com/pricing?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=domain-whois-api-pricing