Ajax Domain Finder

This is a free service that instantly (with ajax) checks domains name availability and some SEO info. If the name your are looking for is taken, you can click on whois...

Free Web

URL Sensei

A JSON API for getting domain whois data and taking website screenshots.

Freemium Web

Domains Index

Lists of all registered domains, registered domains database, bulk WHOIS database.

Freemium Web Self-Hosted

ipdb.me

Domain name, IP, autonomous system research web application.

Free Personal Web

ponderworthys whois

A simple, reliable, and fast lookup, of the whois database systems, for Internet domains. Also has a lookup pulling all DNS records for fully qualified domain names.

Free Web

WhoAPI

Comprehensive API that delivers parsed Whois results, domain availability information, website screenshots, PageRank, Alexa rank, and other domain data.

Freemium Web