Compound Interest Calculator
See the true power of compounding — with an optional monthly contribution to model recurring investments.
Inputs
₹1.00 L
Optional — leave 0 for pure compounding
Compounding frequency
Final amount
₹2,59,374
after 10 years
- Initial principal
- ₹1,00,000
- Total contributions
- ₹0
- Total invested
- ₹1,00,000
- Interest earned
- ₹1,59,374
Formula: A = P(1 + r/n)^(n×t). Contributions are grown separately using the equivalent per-month rate.
Money split
- Initial
- Interest
Total: ₹2.59 L
How the math works
A = P × (1 + r/n)^(n×t) + PMT contributions grown at monthly rate
- P
- Initial principal
- r
- Annual interest rate (decimal)
- n
- Compoundings per year
- t
- Tenure in years
- PMT
- Optional monthly contribution
How it works
- 1
Set your starting amount (can be 0 if you’re only doing monthly contributions).
- 2
Add an optional monthly addition to model recurring investments.
- 3
Choose rate, tenure and how often interest compounds.
- 4
CalcPe grows the initial amount and the contribution stream separately, then sums them.
A quick walkthrough
Inputs
₹1,00,000 initial + ₹5,000/month at 10% p.a. compounded yearly for 20 years.
Steps
- Initial grows: 1,00,000 × 1.10²⁰ ≈ ₹6.73 L
- Contributions grow with per-month equivalent of 10%/yr compounding
- Total ≈ initial future value + contribution future value
Result
Final amount ≈ ₹44–45 lakh depending on exact compounding cadence.
Why CalcPe’s Compound Interest Calculator
- Visualise Warren Buffett’s favourite: the “interest on interest” effect.
- Compare yearly, half-yearly, quarterly and monthly compounding.
- Model recurring deposits, EPF, PPF, mutual funds and more.
- Free, instant and privacy-respecting.