Frequently Asked Questions
Everything you need to know
How does the Mathnal Family Expense Simulator work?
The Mathnal Family Expense Simulator is a free browser-based financial planning tool for Indian families. You enter your family profile (size, age, location, lifestyle), then fill in 30+ expense categories across food, transport, utilities, loans, kids, parents, healthcare and lifestyle. The simulator then projects your expenses across 6 months, 1, 2, 3, 5 and 10 years using inflation coefficients calibrated to Indian RBI/NSSO data. You can stress-test against macro shocks like petrol rise, fertiliser hike, rupee depreciation, gold spike, or war. The Suggestions engine then evaluates whether your savings goals are achievable through earning more, spending less, or both — and tells you which is more realistic for your situation.
Is the Household Planner free?
Yes — 100% free. No signup. No login. No subscription. No data leaves your laptop. The tool runs entirely in your browser. You can save your data to your browser's local storage so it persists between visits, but Mathnal Analytics never sees your numbers. This is part of Mathnal's principle of providing free, evidence-based decision tools to Indian families and businesses.
How does the inflation simulator work?
The inflation simulator applies category-specific inflation rates to each expense, then compounds them over the time horizon you select (6 months, 1, 2, 3, 5, or 10 years). The default inflation rates are calibrated to Indian CPI and RBI data: food at 5.5%/year, fuel at 4-6%/year, healthcare at 8-10%/year (highest), education at 8-9%/year, electricity at 4-5%/year, etc. You can override these defaults if you want to model your own scenarios. The simulator also computes the income growth required to maintain your current savings rate, and flags which expense categories will become unaffordable first.
What macro stress tests does the planner include?
Six macro stress scenarios. (1) Petrol rise — ₹1 to ₹15 per litre, with calibrated pass-through to food, transport, services. (2) Fertiliser hike — ₹100 to ₹500 per bag, mostly hits food prices over 60-90 days. (3) Rupee depreciation — 1% to 10% rupee fall, impacts imported goods (electronics, edible oils, medicines). (4) Gold price rise — 1% to 25%, affects investment planning and marriage budgets. (5) War / geopolitical shock — combined effect of oil + supply chain disruption + rupee weakness. (6) Custom scenario — user-defined combinations of the above. Each scenario shows the absolute and percentage impact on monthly expenses, annual budget, and savings rate.
What does the 'earn-more vs save-more' suggestion do?
After analysing your income, expenses, and savings gap, the Suggestions engine computes two paths to financial health: (1) Earn-more path — how much your income needs to grow to maintain your current lifestyle plus achieve your savings goals, with concrete tactics (skill upgrade, side income, asset deployment). (2) Save-more path — which expense categories have the most slack, ranked by impact and feasibility (e.g., bulk-buying groceries can save ₹400-700/month immediately; downsizing housing takes 6-12 months). It then tells you which path is more realistic for your situation. For most Indian middle-class households, the answer is 'both, but start with save-more because it's faster'.
Does the planner cover children education and marriage planning?
Yes. The Kids section captures current school/college fees, books, transport, tuition, and projects them forward based on each child's age. It models the typical Indian education cost escalation (current fees × 1.08^years for school, × 1.12^years for college). For marriage planning, you enter each child's current age and the planner projects when the marriage event will occur and what the typical Indian middle-class marriage budget will cost at that point (₹15-50 lakh today, inflated forward). Parents care section covers their medical and lifestyle expenses with separate medical inflation curve (8-10%).
What inflation rates are used by default?
Defaults calibrated to Indian CPI and RBI inflation history. Food and groceries: 5.5%/year. Vegetables: 6.5% (more volatile). Meat/fish: 6%. Edible oils: 5%. Fuel and transport: 5%. Electricity: 4%. Water: 3%. Healthcare: 9% (highest of all categories). Medical insurance: 10%. Education (school): 8%. Education (college): 11%. Lifestyle/entertainment: 5%. Marriage budget: 7%. Gold (for marriage/jewelry): 8%. Real estate: 6%. These are user-overridable in the simulator tab. The defaults reflect 10-year India inflation averages with adjustments for category-specific drivers.
How accurate are the suggestions and inflation projections?
The projections are calibrated to historical Indian data (RBI CPI, NSSO HCES, MoSPI) and are accurate as directional estimates — not point forecasts. The real value is comparative — letting you see relative impact of different scenarios on your specific family. Suggestions are rule-based, not AI-generated, and follow well-established personal finance principles (50/30/20 rule, ABC categorisation, dependency ratio adjustments). Use the tool as one input into your financial planning, not as a substitute for talking to a certified financial planner for major life decisions.