Check an IP address

To check if an IP address is listed in HRBL, use the following form:

1. IP address:
2. Proceed:


  1. You can use DNS queries on your mail server to check if a remote SMTP client is listed in HRBL or not. See the usage page.
  2. Since DNS queries are cached it is possible for a few minutes that DNS tells an IP address listed even if it is actually not listed already.