Compound Interest Calculator

How it is calculated

The calculator first estimates how your starting principal grows over the chosen time horizon at the expected return rate. It then estimates the growth of your regular monthly contributions over the same period. These two growth components are combined to show projected value, invested amount, and estimated interest earned.

Assumptions

• Return rate remains constant through the full period.
• Monthly contribution amount is fixed and regular.
• Taxes, charges, and inflation impact are excluded.

Why it matters

This helps compare savings inputs against long-term outcomes and makes compounding effects explicit.