Estimate how much your money market account will earn over time. This tool helps savers, budget planners, and banking customers project returns based on deposit amount, interest rate, and compounding frequency. Use it to compare different account options or plan your savings goals.
Money Market Account Return Calculator
Project your savings growth with compounding interest
Account Details
Ignored if using APY, which already accounts for compounding
Enter your combined federal and state tax rate to calculate after-tax returns
💡 Tip: Money market accounts are FDIC insured up to $250,000, making them low-risk savings options.
How to Use This Tool
Follow these steps to generate accurate return projections for your money market account:
- Enter your initial deposit amount in the first field.
- Add any monthly contributions you plan to make (leave at 0 if none).
- Input the annual interest rate offered by your bank, and select whether it is APY or APR.
- Choose the compounding frequency for your account (this is ignored if you selected APY).
- Set the investment time period and select years or months as the unit.
- Optionally enter your combined tax rate to see after-tax returns.
- Click the Calculate Returns button to view your detailed breakdown.
- Use the Reset Form button to clear all inputs and start over.
Formula and Logic
This calculator uses standard future value formulas for savings accounts with regular contributions:
- Initial deposit growth: Calculated using compound interest formula FV = P * (1 + r)^n, where P is principal, r is periodic rate, n is number of periods.
- Monthly contributions: Treated as an ordinary annuity (contributions made at end of each month) using FV = C * [(1 + r)^n - 1] / r, where C is monthly contribution.
- APY vs APR: APY (Annual Percentage Yield) already accounts for compounding frequency, so the compounding selection is ignored for APY calculations. APR (Annual Percentage Rate) is converted to effective annual rate (EAR) using EAR = (1 + (APR / n))^n - 1, where n is compounding periods per year.
- Tax impact: Taxes are applied only to interest earned, not to your principal or contributions. After-tax balance is total pre-tax balance minus taxes owed on interest.
Practical Notes
Keep these real-world factors in mind when using this calculator:
- Money market account rates are variable: Unlike certificates of deposit (CDs), money market rates can change at any time, so projections are only accurate if rates remain constant.
- FDIC insurance: Most money market accounts are FDIC insured up to $250,000 per depositor, per bank, making them low-risk savings vehicles.
- Minimum balance requirements: Many accounts charge fees if your balance drops below a certain threshold, which can reduce your effective returns.
- Tax reporting: Interest earned on money market accounts is reported on Form 1099-INT, and is taxable as ordinary income at the federal and state level.
- Compounding frequency: Daily compounding (common for money market accounts) earns slightly more interest than monthly or quarterly compounding at the same APR.
Why This Tool Is Useful
This calculator helps you make informed decisions about your savings strategy:
- Compare different money market account offers by adjusting rate, compounding frequency, and fees.
- Plan monthly contributions to reach specific savings goals, such as a down payment or emergency fund.
- Understand the impact of taxes on your returns, especially for high-yield accounts.
- Project long-term growth to align with retirement or education savings plans.
- Avoid overcomplicating calculations with manual spreadsheet formulas.
Frequently Asked Questions
Is interest earned on money market accounts taxable?
Yes, interest earned on money market accounts is taxable as ordinary income at the federal level, and may also be subject to state and local taxes. This calculator lets you enter your combined tax rate to see your after-tax returns.
What is the difference between APY and APR for money market accounts?
APY (Annual Percentage Yield) includes the effect of compounding interest, so it reflects the actual amount you will earn in a year. APR (Annual Percentage Rate) is the base interest rate without compounding, so you will earn less than the APR if compounding is less than annual. Most banks quote APY for money market accounts.
Can I use this calculator for other savings accounts?
Yes, this calculator works for any savings vehicle that uses compound interest, including high-yield savings accounts, certificates of deposit (CDs), and cash management accounts. Adjust the inputs to match the terms of your specific account.
Additional Guidance
To get the most accurate results from this tool:
- Check your most recent bank statement to confirm your exact APY/APR and compounding frequency.
- Include any monthly fees in your contribution calculations (e.g., subtract $10 monthly fee from your $200 contribution to get a net $190 contribution).
- Recalculate every 3-6 months if interest rates change, to keep your projections up to date.
- Consider using conservative rate estimates if you plan to hold the account for many years, as rates may decrease over time.