Guides and explainers behind the numbers — how our calculators actually work.
Tables up to 10 contain 100 facts, but a child who knows the easy tables and uses turn-arounds has only 21 left to learn. Here is a learning order, a trick for each table and a five-minute daily routine.
Your phone can pin you to within 5 to 20 metres, but a laptop may be off by a kilometre. Here is how to read latitude and longitude, when to send a fixed pin or a live location, and how to share it safely.
A ₹12 lakh CTC does not mean ₹1 lakh a month. With a typical salary structure it is closer to ₹85,000. Here is where the rest goes, with figures for common CTCs.
Ten years of service on a last basic pay of ₹40,000 earns a gratuity of about ₹2.31 lakh. Here is the formula, who is eligible, the ₹20 lakh limit and how gratuity is taxed.
A ₹2 lakh prepayment in the first year of a ₹40 lakh home loan saves over ₹7 lakh in interest. The same amount paid in year ten saves about a third of that. Here is why timing matters.
A 1.5 ton AC running 8 hours a day can use 150 to 360 units a month depending on the model. Here is how to work out the units, the cost, and how to bring the bill down.
Non-government NPS subscribers now need to annuitise only 20% of their corpus at 60, and a corpus up to ₹8 lakh can be withdrawn in full. Here is what changed.
Salary up to ₹12.75 lakh now pays no income tax under the New Regime. Here is the tax at common salary levels, and when the Old Regime still wins.
20% off plus another 10% off isn't 30% off. Here's the correct math for discounts, including the stacked-discount trap.
A ₹5,000 SIP doesn't just add up to what you put in — compounding does a lot of the heavy lifting. Here's the formula behind the numbers.
Trying to conceive (or avoid it) starts with knowing when ovulation actually happens. Here's the calendar-based method and its limits.
Your due date isn't a guess pulled from thin air — it's based on a 200-year-old rule and one date you already know. Here's the math.
Working out hours and minutes between a start and end time seems simple, until the shift crosses midnight. Here's the method that always works.
Counting age by hand gets messy once leap years and differing month lengths are involved. Here's the logic behind getting it exactly right.
No spreadsheets, no complicated categories — just three buckets. Here's how the 50/30/20 rule works and how to apply it to your paycheck.
ROI turns any gain or loss into one comparable percentage. Here's the formula, a worked example, and where it falls short.
Basal Metabolic Rate is the starting point for every calorie goal — weight loss, maintenance, or muscle gain. Here's how it's worked out.
Quick mental-math shortcuts for tips, discounts, and everyday percentage problems — no calculator required (usually).
Same principal, same rate, same time — but very different results. Here's why compounding matters so much over the long run.
Whether you're adding GST to a price or extracting it from a GST-inclusive amount, here's the math behind it.
BMI is one of the simplest health screening numbers there is. Here's what it actually measures, and where it falls short.
A plain-English walkthrough of the EMI formula, what drives your monthly payment up or down, and a worked example.