How to enter it
Set the starting amount, monthly contribution, annual rate, and years. Then choose daily compounding in the compounding menu.
dailyRate = annualRate / 365balance = balance x (1 + dailyRate) ^ days + depositDaily deposits estimate
Daily compound interest calculator with contributions
Use this page when the account compounds daily and you also plan to add money every month. The main calculator can model that setup with a growth curve and a contribution breakdown.
Worked example
A $5,000 starting balance, $250 monthly deposit, 7% annual return, and 20-year timeline can grow much more from consistent deposits than from the first balance alone.
The contribution chart on the main calculator separates total deposits from estimated growth, which makes the tradeoff easier to see.
What matters most
Daily compounding is only one lever.
For most long-term savings plans, the biggest drivers are time, deposit size, and the assumed annual rate. Compounding frequency usually matters less than people expect.
Decision guide
Contribution timing changes the projection
Daily interest and monthly deposits operate on different schedules. A deposit made at the start of a month earns longer than the same deposit made at month-end. For realistic planning, choose one timing convention, use it consistently, and treat the result as a scenario rather than a promise.
Separate deposits from growth
If you start with $5,000 and add $200 monthly for five years, your direct contributions equal $17,000 before interest. The calculator's ending balance above that amount is modeled growth. Showing those two components prevents a common mistake: attributing every dollar of the final balance to compounding.
Before you decide
- Use the date deposits actually arrive.
- Keep daily rate and annual rate conversions consistent.
- Test a lower-rate case for variable savings products.
- Include missed deposits as a separate scenario.
Method and limitations
Investor.gov explicitly models monthly contributions apart from the initial investment. This tool follows the same planning logic while applying the selected compounding convention. Actual institutions may use daily balances, credit interest monthly, change rates, or apply balance tiers, so statements can differ from a smooth projection.