How to use this calculator
- Enter first-year monthly deposit, annual deposit increase (%), nominal annual rate (%), monthly periods.
- Choose a display currency, then select Calculate. Results also update after a brief pause while you edit.
- Read the result with the assumptions below. Export details or save a second scenario to compare your choices.
Formula and method
Assumptions and limitations
Step increases occur after every completed twelve-month block. Returns are a constant scenario; no fund fees, tax or missed contributions.
Worked example
At 0%, twelve deposits of 100 followed by twelve of 110 produce 2,520 after two years.
What the result means
Project recurring investments when the monthly deposit increases every twelve months.
Common questions
How is the calculation performed?
Monthly deposit in year k = starting deposit × (1 + annual step)^(k−1); apply monthly return and add each deposit at month-end.
What does the model leave out?
Step increases occur after every completed twelve-month block. Returns are a constant scenario; no fund fees, tax or missed contributions.
Methodology and transparency
Calculation specification reviewed on 2026-10-14. Mathematical implementation is tested against independent reference fixtures. This does not imply review by a licensed financial professional. Read the testing and precision policy.