Money Market Fund Calculator
Compute future value with contributions, global currencies, flexible compounding, and net APY after fees/taxes. Outputs are illustrative.
Final balance (nominal)
Total contributions
Total interest earned
Real balance (inflation‑adjusted)
Effective net APY
Real net APY
Money Market Fund Calculator — How to Calculate MMF Returns
A Money Market Fund (MMF) Calculator helps you estimate how much interest your investment can earn over time. It shows monthly interest, annual returns, and the effect of compounding based on your investment amount, interest rate, and duration.
This calculator is useful if you want to know how much interest you’ll earn, your final balance, or your effective annual yield.
Money Market Fund Compound Interest Formula
Most money market fund calculators use the compound interest formula:
Formula:
A = P × (1 + r / n)^(n × t)
Where:
- A = Final amount (total balance after interest)
- P = Principal (initial investment)
- r = Annual interest rate (as a decimal)
- n = Number of compounding periods per year (usually 365 for daily compounding)
- t = Time in years
Example: Daily Compounding MMF Calculation
If you invest Ksh 100,000 at 10% annual interest, compounded daily for 1 year:
A = 100,000 × (1 + 0.10 / 365)^(365 × 1)
A ≈ 110,515
Interest earned:
110,515 − 100,000 = Ksh 10,515
This is how a money market fund calculator estimates your annual return.
Monthly Money Market Interest Formula
To estimate monthly interest (before compounding):
Formula:
Monthly Interest = (Principal × Annual Rate) ÷ 12
Example:
If you invest Ksh 500,000 at 10% annually:
Monthly Interest = (500,000 × 0.10) ÷ 12
Monthly Interest ≈ Ksh 4,166.67
This is what a money market monthly interest calculator displays.
Daily Money Market Interest Formula
Money market funds often calculate interest daily.
Formula:
Daily Interest = Principal × (Annual Rate ÷ 365)
Example:
Annual rate = 10%
Principal = Ksh 200,000
Daily Rate = 0.10 ÷ 365 = 0.000274
Daily Interest = 200,000 × 0.000274
Daily Interest ≈ Ksh 54.80
For 30 days:
54.80 × 30 ≈ Ksh 1,644
Effective Annual Yield (EAY) Formula
The Effective Annual Yield (EAY) shows your true annual return after compounding.
Formula:
EAY = (1 + i / n)^n − 1
Where:
- i = Nominal annual interest rate
- n = Compounding periods per year
Example:
At 10% interest, compounded daily:
EAY = (1 + 0.10 / 365)^365 − 1
EAY ≈ 10.52%
This explains why MMFs earn slightly more than the stated rate.
7-Day Yield Explained (Simple)
The 7-day yield shows the average interest earned over the last 7 days, then annualized.
Formula (simplified):
7-Day Yield = (Income earned in 7 days ÷ Investment) × (365 ÷ 7)
It helps investors compare short-term performance between funds.
Summary of Money Market Calculator Formulas
| Calculation | Formula |
|---|---|
| Compound Interest | A = P × (1 + r / n)^(n × t) |
| Monthly Interest | (Principal × Annual Rate) ÷ 12 |
| Daily Interest | Principal × (Annual Rate ÷ 365) |
| Effective Annual Yield | (1 + i / n)^n − 1 |
Why Use a Money Market Fund Calculator?
- Estimate monthly and annual returns
- Understand daily compounding effects
- Compare MMF rates easily
- Plan short-term investments with confidence
Whether you’re investing Ksh 10,000 or Ksh 3 million, a money market fund calculator removes guesswork and shows exactly how your money grows.