Rentable Square Footage Calculator

How to Use This Calculator

1. Enter the Usable Square Footage of your commercial space. This is the area specifically designated for your use.
2. Enter the Common Area Factor percentage. This is typically provided by your landlord or building management and represents the percentage of total building square footage that is shared among all tenants (e.g., lobbies, hallways, restrooms).
3. Click the Calculate button to compute the rentable square footage and total building square footage.
4. The results will show how much of your rent is based on the total building square footage, not just your usable space.

Understanding Rentable Square Footage

Rentable square footage is typically larger than your usable square footage because it includes your share of common areas. Commercial buildings use this measurement to calculate rent, as it represents the total space you're paying for, even if you don't directly occupy it.

Example

If you have 1,000 sq ft of usable space with a 20% common area factor, your rentable square footage would be:

1,000 sq ft × (1 + 20/100) = 1,000 sq ft × 1.20 = 1,200 sq ft

This means you would be paying rent based on 1,200 sq ft, even though you only occupy 1,000 sq ft.