I just compared those numbers with the tax calculator from https://simpletax.ca/calculator and they are roughly the same. However, my numbers line up with that when you factor in tax deductible expenses on things like RRSP. If you remove the RRSP line from the expenses table, you should see that 100k in base salary lines up to the articles claimed $27.7k. The numbers arent exact, but they are pretty close. I will look further into the discrepancy.