Computing your income tax depends on different tax options you choose - in Taxumo, you do this via your Taxpayer/Company profile.

Here are the different scenarios:

Scenario #1: You are earning purely from your business/profession AND you are using  the 8% Flat Income Tax Rate

Example:
Total Income: Php 1,000,000.00
Total Expense: Php 360,000.00

Taxable Income = (Php 1,000,000 - Php 250,000) = Php 750,000

Tax Due = Php 750,000 * 8% = Php 60,000

Scenario #2: You are a mixed income earner (meaning some of your income comes from compensation) and you are using 8% Flat Income Tax Rate

Example:
Total Income: Php 1,000,000.00
Total Expense: Php 360,000.00

Taxable Income = Php 1,000,000

Tax Due = Php 1,000,000 * 8% = Php 80,000

Scenario #3: You are using Graduated Income Tax Rate (not the 8%) and you have opted for Optional Standard Deduction (OSD)

Example:
Total Income: Php 1,000,000.00
Total Expense: Php 360,000.00

Taxable Income = Php 1,000,000 * 60% = Php 600,000

Tax Due = Php 30,000 + (25% * Php 600,000 - Php 400,000)*
Tax Due = Php 80,000

*as per TRAIN updated income tax table

Scenario #4: You are using Graduated Income Tax Rate and you are using Itemized deduction instead of OSD

Example:
Total Income: Php 1,000,000.00
Total Expense: Php 360,000.00

Taxable Income = Php 1,000,000 - Php 360,000 = Php 640,000

Tax Due = Php 30,000 + (25% * Php 640,000 - Php 400,000)*
Tax Due = Php 90,000

*as per TRAIN updated income tax table

Related Article:
​Can I File My Annual Income Tax Return via Taxumo