Our assumptions and calculations.

Starting assumptions

Annual salary inferred from a verified monthly salary is monthly in-hand × 12. When an investment or liquid opening balance is missing, the projection starts that balance at zero. Goal pages also have separate workbook sample inputs listed below. These figures are planning examples, not forecasts.

Every sample input

These are the example inputs used when a saved value is missing; some fields are overridden by your shared profile or another goal. All rates below are displayed as percentages. For fields without a currency or age unit in the label, values use rupees, years or age according to the named input.

The standalone Loan / EMI and Passive Income pages begin with blank balances and user-editable 8.5% interest/10 years or 6% yield/10 years respectively. Their calculations rely on entered values, not implied corpus or outstanding debt.

Annual Master cash flow

Each year starts with salary and other income, including timed passive payouts while their holding period is active. We subtract annual spending, goal costs, home down payment, mortgage payments, existing loan payments, and SIP contributions. Cash left goes into the liquid balance. The invested balance grows using the saved return rate; a separate held passive-income principal is excluded from that growth during the holding period. After its payouts end, the principal returns to the regular invested corpus.

The projected net worth is closing investments + closing liquid balance + home value − home mortgage balance − remaining balances on existing loans. At retirement, salary uses the saved post-retirement income and SIP contributions stop. If annual cash flow is negative, the model draws on investments to cover a negative liquid balance where possible.

Loans and passive income

A fixed-payment loan's monthly interest is opening balance × annual rate ÷ 12. The payment covers interest first; the remainder reduces principal. The EMI suggestion uses the standard amortizing-payment equation: balance × monthly rate ÷ (1 − (1 + monthly rate)^−months), or balance ÷ months when the rate is zero. The plan shows actual entered payments and stops them on payoff. A payment that leaves a balance at the end of its remaining term cannot be saved through the loan simulator.

Passive monthly income is lump sum × annual yield (%) ÷ 1,200. It runs for the saved whole-year holding period. The lump sum must already be included in the shared investment balance; the income is separate from the principal. This assumes a fixed payout and no tax, fees, reinvestment, default risk or yield changes. Microsoft's PMT reference explains the fixed-payment convention.

Goal formulas and limits

Child Wealth: yearly SIP = monthly SIP × 12 × (1 + SIP increase)^{years since child's starting age}. School, college and marriage costs occur in their entered age windows and grow by their separate inflation rates. Closing fund = opening fund + annual SIP − goal withdrawals + expected return × (opening fund + annual SIP − withdrawals).

Home Purchase: deposit = property price × down-payment share; mortgage balance = purchase price − deposit. Each EMI covers interest first, then principal. Home equity = appreciated property value − remaining mortgage. Rent increases by the saved rent-growth rate. The renter's investment alternative starts from the deposit and compounds the selected stock return, adjusted each year for the difference between ownership cost and rent. Salary affordability compares monthly EMI with annual salary ÷ 12. Optional prepayments reduce the ending mortgage and add to the year's cash outflow; purchase-delay, rate, price, deposit and tenure scenarios recalculate these results independently.

Emergency Fund: runway = liquid corpus ÷ monthly essential expenses when expenses are above zero; the target equals six months of essentials, and the gap is the positive difference between target and existing liquid funds. Retirement: salary becomes saved annual post-retirement income at the selected age; regular SIP stops and the negative liquid balance draws from investments until depleted. Master scenarios are unsaved drafts changing purchase delay, deposit, mortgage rate, home price, annual prepayment, invested return or expense inflation one at a time.

Years are annual approximations, and rounding is for display. Marriage and expected child dates appear on the timeline, but they do not automatically create a new cost or a child SIP; enter these separately in your goal plan. Life events can fall in the same calendar year. Future rates, inflation, market results, taxes, fees and personal needs can differ greatly from these illustrations.

Reference spreadsheets: Child Wealth, Home Purchase, Life Financial.