Last reviewed: 10 September 2026. This page describes the identities already implemented in the JavaScript engines. Formulas were not changed to chase ads or search rankings.
Grow Money Calculator is a planning website, not a bank, AMC or insurer. Every tool uses the numbers you type. Default rates (for example 7.75% on a home loan or 7.1% on PPF) are illustrations so the sliders have a starting point. They are not “today’s” market or notified rates unless you replace them with a quote you actually received.
| Family | What the engine does | What it does not do |
|---|---|---|
| Loan EMI | Reducing-balance instalment from P, annual rate and years. | Credit score, LTV, fees, pre-EMI during construction unless you lower P. |
| Eligibility | Inverts EMI from leftover FOIR capacity. | A sanction, employer check or bureau pull. |
| Affordability | Inverts an EMI budget and a down-payment percent into a price sketch. | Stamp duty schedules for every state. |
| SIP / lumpsum | Compounds the contribution or corpus at the rate you typed. | Live NAV, expense ratio or tax on gains. |
| FD / RD | Compounding at the frequency you choose. | TDS, premature-break penalty, bank-specific payout. |
| PPF | Yearly deposit then an annual rate you type. | The notified rate on a given date unless you enter it. |
| Tax sketches | 80C bucket, HRA three-way minimum, GST percent, stamp percent. | ITR filing or the latest Finance Act until you verify. |
Reducing-balance EMI: EMI = P × r × (1+r)^n / ((1+r)^n − 1), where r is annual percent ÷ 12 ÷ 100 and n is months. Year-wise amortization uses that EMI against opening principal. Zero rate is a simple P/n split in the engine. Processing fees, GST, insurance and pre-EMI are not added unless a specific tool says so.
Check: ₹10,00,000 at 7.2% for 10 years gives EMI ≈ ₹11,714, total payable ≈ ₹14,05,702, interest ≈ ₹4,05,702 on this identity. The home loan page uses the same function as personal and car loan pages; only defaults and surrounding copy change.
Eligibility inverts the EMI formula from leftover FOIR capacity. Affordability inverts from an EMI budget and grosses up by a down-payment percent. Neither is a credit decision.
SIP uses a monthly compounding annuity with optional yearly step-up. Lumpsum is (1+r)^t. FD is P × (1 + r/m)^(m×t). PPF adds a yearly deposit then applies an annual rate. Expected investment returns are assumptions, not NAV history.
Display rounding may differ from a lender’s paise rounding. Multi-currency mode converts displayed INR-based results with hard-coded approximate FX — not a live feed.
They do not sanction a loan, allot units, guarantee FD interest after TDS, or replace a tax working paper. Read the disclaimer and editorial policy.
Contact: experts@growmoneycalculator.com.