Guides
How things work, with real numbers. Each guide shows the working, and every example is verified against the matching tool.
How to Calculate EMI by Hand
Learn the EMI formula with a worked example: ₹1,00,000 at 12% for 12 months is ₹8,884.88 a month. See each step, plus the zero-interest case.
Read the guideHow to Calculate Your Age in Days
Subtract your date of birth from today's date, counting leap days exactly. Example: 1 Jan 2000 to 1 Jan 2025 is 9,132 days. See the 29 Feb rule.
Read the guideCGPA to Percentage: The CBSE ×9.5 Rule, Explained
CGPA × 9.5 gives an estimated percentage under the CBSE convention: 8.0 CGPA is about 76%. Learn why it is an estimate, and when your own rule differs.
Read the guideEMI Calculator vs Mortgage Calculator: Which One to Use
Same formula, different presentation: the EMI page uses ₹ and Indian loan language; the Mortgage page uses $ and US mortgage language. Pick by currency.
Read the guideHow to Choose an EMI Calculator
Every EMI calculator runs the same formula. What differs: total interest display, amortization view, prepayment, currency. Five checks that separate honest tools from traps.
Read the guideCalculate Age in Excel: 3 Formulas That Work
DATEDIF gives exact years, months and days: =DATEDIF(A2,TODAY(),"Y"). YEARFRAC gives decimals. Plus the 30-second rough method and the errors everyone hits.
Read the guideIs BMI Accurate? What the Number Can't Tell You
BMI is a screening tool, not a diagnosis. It misreads athletes, older adults, and muscular builds. What it gets right, where it fails, and what doctors check instead.
Read the guideHow to Calculate BMI by Hand: Formula, Examples, Metric and Imperial
BMI = weight ÷ height². Worked examples in kilograms and pounds, the WHO bands explained, and the mistakes that give wrong numbers.
Read the guideHow Many Words Fit on a Page?
About 500 words on a single-spaced page, about 250 double-spaced (12pt type, 1-inch margins). See the line-by-line math, font differences, and the manuscript standard.
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