WHOIS Server(s) & Information
Domain Extension  WHOIS Server (Port 43) Match String Transfer  Min-Max Yrs
   Registrar WHOIS Server  whois.dnapi.net      
  com  whois.crsnic.net  No match for Yes 1 - 10
  net  whois.crsnic.net  No match for Yes 1 - 10
  org  whois.publicinterestregistry.net  NOT FOUND Yes 1 - 10
  biz  whois.neulevel.biz  Not found Yes 1 - 10
  info  whois.afilias.info  NOT FOUND Yes 1 - 10
  name  whois.nic.name  No match Yes 1 - 10
  mobi  whois.dotmobiregistry.net  NOT FOUND Yes 1 - 10
  asia  whois.nic.asia  NOT FOUND Yes 2 - 10
  travel  whois.nic.travel  No match Yes 1
  jobs  jobswhois.verisign-grs.com  No match Yes 1 - 10
  aero  whois.aero  NOT FOUND Yes 1 - 10
  eu  whois.eu  FREE Yes 1
  co.uk  org.uk  me.uk  whois.nic.uk  No match Yes 2 - 2
  nu  whois.nic.nu  NO MATCH Yes 2 - 2
  cc  ccwhois.verisign-grs.com  No match Yes 1 - 10
  us  whois.nic.us  Not found Yes 1 - 10
  de  whois.denic.de  ** Yes 1 - 1
  se  whois.nic-se.se  No data found Yes 1 - 1
  ws  whois.nic.ws  No match No 1 - 10
  fm  whois.nic.fm  No match Yes 1 - 5
  am  whois.nic.am  No match No 1 - 5
  tv  tvwhois.verisign-grs.com  No match Yes 1 - 10
  la  whois.centralnic.net  No match for Yes 1 - 10
  md  whois.mdnet.md  not found No 1 - 10
  sc  com.sc  net.sc  org.sc  whois2.afilias-grs.net  NOT FOUND Yes 1 - 10
  bz  whois2.afilias-grs.net  NOT FOUND Yes 1 - 10
  jp  whois.jprs.jp  No match No 1 - 2
  gl  whois.nic.gl  No match Yes 1 - 2
  cn  com.cn  net.cn  org.cn   whois.cnnic.net.cn  no matching record Yes 1 - 5
  com.tw  org.tw  idv.tw  club.tw  ebiz.tw game.tw  whois.twnic.net.tw  Not Found Yes 1 - 5
  sg  com.sg  whois.nic.net.sg  NOMATCH No 1 - 2
  pl  com.pl  net.pl  org.pl  biz.pl  info.pl  whois.dns.pl  No information Yes 1 - 3
  ag  com.ag  net.ag  org.ag  whois2.afilias-grs.net  NOT FOUND Yes 1 -10
  in  co.in  net.in  org.in  firm.in  gen.in  ind.in  whois.inregistry.in  NOT FOUND Yes 1 - 5
  at  co.at  or.at  whois.nic.at  nothing found Yes 1 - 1
  be  whois.dns.be  FREE Yes 1 - 1
  tk  whois.dot.tk  Invalid query No 2 - 2
  tc  whois.adamsnames.tc  not registered Yes 1 - 1
  vg  whois.adamsnames.tc  not registered Yes 1 - 1
  ms  whois.adamsnames.tc  not registered Yes 1 - 1
  gs  whois.nic.gs  No match No 1 - 1
  sh  whois.nic.sh  No match No 1 - 1
  ac  whois.nic.ac  No match No 1 - 1
  io  whois.nic.io  No match No 1 - 1
  tm  whois.nic.tm  No match No 5 or 10
  vc  com.vc  net.vc  org.vc  whois2.afilias-grs.net  NOT FOUND Yes 1 - 10
  ru  whois.ripn.net  No entries found No 1 - 1
  it  whois.nic.it  No entries found No 1 - 1
  nl  whois.domain-registry.nl  is free No 1 - 1
  es com.es  net.es  org.es  **  ** No 1 - 1
  im  whois.nic.im  ** No 1,2,5,10
  mn  whois2.afilias-grs.net  NOT FOUND Yes 1 - 10
  cx  whois.nic.cx  Not registered No 1 - 1
  mu com.mu net.mu org.mu  whois.nic.mu  Not registered No 1 - 1
  ki com.ki net.ki org.ki  whois.nic.ki  Not registered No 1 - 1
  nf com.nf net.nf  whois.nic.cx  Not registered No 1 - 1
  tl  whois.nic.tl  Not registered No 1 - 1
  com.mx  whois.nic.mx  No Encontrado No 1 - 1
  co.nz net.nz org.nz  whois.srs.net.nz  220 Available No 1 - 1
  CentralNIC (third level domains)  whois.centralnic.net  No match for Yes 1 - 10
 
 ** Either the TLD does NOT offer any WHOIS Server or the server is highly restrictive. In either case, the API (command = CheckDomain) should be used for domain availability checks. (NOTE: The API is always preferred)

 AWBS Users - If you prefer to use iRRP.Net API (CheckDomain) for your domain availability checks, enter irrp under Whois Server, the response strings are not relevant.

Note: Using iRRP for your lookups will be more accurate than the various whois servers, however it take longer for the results with SOME TLDs, while other TLDs the API is much quicker the the WHOIS. If you offer many tlds, you may want to use irrp only for the most popular ones to keep the process quick enough and avoid apache/IIS timeouts.