Based on the information found on the official website, the software provides information about tides in over 7000 ports. I didn't see anything related to the calculation of the tide. However, it will display the tide based on the location you enter. Additionally, you have the possibility to download a trial version of the software. Access the official website, then click on the Downloads tab and follow the instructions.
Download instructions:
URL: FTP://ukho.gov.uk
Username: ukhopublic
Password: Public12345
Note: The username and password details are case sensitive.