If you are looking for a project to download and run, these are the most common open-source or commercial options that provide a ZIP package:
FoxWhois 2.5.3 free (Windows) Download foxwhois_free_2.5.zip. WP Domain Checker - Curve Studio Download domain checker zip
: For hosting providers, the Realtime Register module for WHMCS comes as a plug-and-play ZIP file with installation instructions. If you are looking for a project to
: A free plugin with premium features that requires downloading the ZIP from Curve Studio for installation. Download domain checker zip