It's based on your office space in relation to the total area of your home. For example, if your home office is 100 sq. ft. and your total home is 2000 sq. ft.. then it is 5%. The software will calculate the percentages.
There are two ways to deduct home office expenses. One is
using Actual Expenses and the other is the Simplified method. Which
one you use depends on the amount of your expenses and the size of your office
The Actual Expense method uses the business use percentage of your actual costs (utilities, mortgage interest/rent, insurance, etc.) based on the square footage of your home office compared to your total home. The Simplified method is $5/sq ft up to 300 sq ft of office space.
To take a deduction for your home office, you must regularly use a portion of your home exclusively for conducting
it must be your principal place