Calculation standards

How QuickCalcy calculates results.

QuickCalcy uses common financial mathematics conventions for educational estimates. The calculators are built to show directionally useful results, not official quotes. Small differences can occur when banks, fund houses or government schemes use exact dates, daily balances, rounding rules, taxes, charges or product-specific terms.

EMI calculator

EMI uses the standard monthly reducing-balance formula: EMI = P x r x (1 + r)^n / ((1 + r)^n - 1). P is the loan amount, r is the monthly interest rate, and n is the total number of monthly payments. The result excludes processing fees, insurance, prepayments, payment holidays and future floating-rate changes.

SIP and step-up SIP calculators

SIP projections use monthly compounding with contributions assumed at the beginning of each month. Step-up SIP increases the monthly contribution after every 12 contributions. These assumptions make the calculator useful for scenario comparison, but they do not predict mutual fund returns.

Lumpsum and compound interest calculators

The lumpsum calculator uses annual compounding. The compound interest calculator lets users choose annual, half-yearly, quarterly or monthly compounding. Real products may use different day-count rules, tax treatment or interest-crediting schedules.

SWP and FIRE calculators

SWP applies monthly growth before each end-of-month withdrawal and prevents withdrawals from exceeding the available corpus. FIRE inflates current expenses to the retirement year and divides annual expenses by the selected withdrawal-rate assumption. Neither method guarantees retirement sustainability.

NPS and PPF calculators

NPS estimates monthly contribution growth and then splits the projected corpus between lump sum and annuity using user inputs. PPF assumes yearly contributions are made early enough to earn a full year of interest at one constant rate. Actual NPS exit rules, annuity quotes, PPF rates and tax rules can change.

Rent vs buy calculator

The rent-versus-buy calculator compares projected net worth after home growth, outstanding loan balance, purchase costs, maintenance, rent growth and investment return on the cash-flow difference. It excludes taxes, transaction selling costs, broker fees and personal lifestyle preferences.