Canadian Tax Calculator is a Home & Education software developed by Canadian Mind Products. After our trial and test, the software is proved to be official, secure and free. Here is the official description for Canadian Tax Calculator:

EditByMarydown: Calculates Canadian sales taxes: GST HST and PST.

Java Applet that can also be run as an application.
Requires Java version 1.5 or later.

Java source code and sample HTML included.

This version computes by adding GST HST and PST to a base
price. It als works in reverse given the
final price working backwards to get the taxes and base
price. In other words it will tell you the sticker
price to make something come out even after taxes are added.

The distributed version is absolutely identical to the
registered version, and includes Java source and sample
HTML. You may use the code freely in your own programs. You
don't need to register multiple copies.

To install, Extract the zip download with WinZip, available from
http://www.winzip.com (or Similar UnZip utility) into any
directory you please, often C: -- ticking off the (user
folder names) option. To run as an application, type:

java -jar C:commindprodcanadiantaxcanadiantax.jar

adjusting as necessary to account for where the jar file is.

You can run the program without installing it as an Applet at
http://mindprod.com/applet/canadiantax.html