Money guides
Short, practical answers to questions people search before opening a calculator — prepayment vs investing, SIP for ₹1 crore, old vs new tax regime, rent vs buy, and more.
Each guide explains the idea in plain language, shows a worked example where helpful, and links to beMyCalc tools so you can plug in your own amounts. We publish 19 guides covering India and global scenarios.
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Popular guides for your region — open one, then use the linked calculator with your numbers.
- What Is CAGR and How Do You Calculate It?
CAGR is the steady yearly rate that would grow your starting value to your ending value over a period. If ₹1 lakh became ₹2 lakh in 5 years, CAGR is about 14.9% — not the simple 20% average return.
- How Much Money Do You Need to Retire?
Retirement planning starts with future monthly expenses, not today's rent. Inflation can triple your need over 30 years. A common target is 25× your annual expenses at retirement — then work backwards to a monthly SIP.
- Rent vs Buy a Home — Which Costs Less?
Buying builds equity but ties up down payment and adds interest. Renting is flexible but builds no ownership. Over 10 years, compare total rent vs mortgage paid minus estimated home value — our rent vs buy calculator shows which side wins under your assumptions.
- Is Home Loan Prepayment Worth It?
Prepaying a home loan saves guaranteed interest equal to your loan rate. Investing may earn more if returns beat the loan rate after tax — but with risk. On an 8.5% loan, a ₹2 lakh prepayment can save ₹3–4 lakh in interest over the remaining tenure; use the prepay vs invest calculator with your outstanding balance and horizon.
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Investing & SIP
SIP targets, CAGR, compound growth, and compare tools.
Investment Calculators →
Loans & EMI
Home loan EMI, eligibility, prepay vs invest, car loans.
Loan & EMI Calculators →
India tax
Old vs new regime, GST, HRA, and take-home salary.
India Tax Calculators →
Retirement
Corpus planning, emergency fund, NPS, and FIRE.
Retirement Planning Calculators →
All guides
Global guides appear for everyone. India guides (₹ examples, local tax rules) show when your currency or region is set to India.
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What Is CAGR and How Do You Calculate It?
CAGR is the steady yearly rate that would grow your starting value to your ending value over a period. If ₹1 lakh became ₹2 lakh in 5 years, CAGR is about 14.9% — not the simple 20% average return.
How Much Money Do You Need to Retire?
Retirement planning starts with future monthly expenses, not today's rent. Inflation can triple your need over 30 years. A common target is 25× your annual expenses at retirement — then work backwards to a monthly SIP.
Rent vs Buy a Home — Which Costs Less?
Buying builds equity but ties up down payment and adds interest. Renting is flexible but builds no ownership. Over 10 years, compare total rent vs mortgage paid minus estimated home value — our rent vs buy calculator shows which side wins under your assumptions.
Is Home Loan Prepayment Worth It?
Prepaying a home loan saves guaranteed interest equal to your loan rate. Investing may earn more if returns beat the loan rate after tax — but with risk. On an 8.5% loan, a ₹2 lakh prepayment can save ₹3–4 lakh in interest over the remaining tenure; use the prepay vs invest calculator with your outstanding balance and horizon.
How Much Emergency Fund Do You Need?
A common target is 3–6 months of essential monthly expenses in a liquid account (savings FD or liquid fund). If expenses are ₹50,000/month, aim for ₹1.5–3 lakh. Self-employed or single-income households often need the higher end — use the emergency fund calculator with your rent, EMIs, and food costs.
How Mortgage EMI Works — Monthly Payment Explained
Mortgage EMI combines principal repayment and interest into one fixed monthly payment. A $300,000 loan at 6.5% for 30 years costs about $1,896/month — most early payments go to interest. Shorter terms raise EMI but cut total interest sharply.
Credit Card Payoff — Avalanche vs Snowball
The avalanche method pays the highest-interest card first and usually saves the most money. The snowball method clears the smallest balance first for psychological wins. On $8,000 across two cards at 22% and 18%, paying $400/month with avalanche can finish months earlier than minimum-only payments.
Compound Interest — How Your Money Grows Over Time
Compound interest means you earn returns on your returns. $10,000 at 8% for 20 years becomes about $46,600 without adding another dollar — versus $26,000 with simple interest. Starting earlier matters more than chasing a slightly higher rate.
How Much Down Payment Do You Need to Buy a Home?
A 20% down payment avoids private mortgage insurance (PMI) in many markets and lowers your loan amount. On a $400,000 home, 20% down ($80,000) versus 10% ($40,000) can save hundreds per month in EMI and PMI — but ties up more cash upfront.
Debt-to-Income Ratio — What Lenders Look For
Debt-to-income (DTI) ratio is total monthly debt payments divided by gross monthly income. Many lenders prefer DTI under 43% for mortgages — including the new housing EMI. If you earn $6,000/month gross and pay $1,800 in debts, DTI is 30%.
Age Calculator by Date of Birth — Exact, Chronological & Birthday Age Explained
An age calculator by date of birth turns your birth date (and optional birth time) into exact calendar age — years, months, and days — plus total days lived, next birthday countdown, and milestone dates. Chronological age is the same everyday count used on forms, school enrollment, and retirement planning; it is not the same as biological or pet-age equivalents. Use our Age Calculator for live seconds, leap-year-correct results, and a shareable link.
How these guides relate to calculators
- Guides explain concepts; calculators produce numbers from your inputs.
- Formulas and assumptions are documented on each calculator — see our methodology.
- Nothing here is tax, legal, or investment advice — estimates for planning only.