Practical guides
Useful context for the result on your screen.
These guides are written around real decisions people make with our tools. Where a topic needs an authoritative source, we link to the original organisation so you can read further.
Unit conversion: choose the units before you do the maths
A practical guide to selecting the right measurement category, units, and level of precision.
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How to calculate the time between two times
A clear method for ordinary time spans, overnight shifts, and time blocks that include breaks.
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GST calculator: understand tax-added and tax-included prices
Use the right calculation for a taxable amount versus a total that already includes the GST rate you entered.
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Percentage calculator: three questions to set up correctly
A practical way to identify the percentage, the part, and the whole before you calculate.
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How to count days between two dates without an off-by-one mistake
Learn the difference between elapsed days and inclusive date counting before a timeline or deadline matters.
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Discount calculator: check the sale price and the saving
A clear way to calculate a sale price, compare offers, and avoid adding successive discounts incorrectly.
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Home loan EMI: compare tenure before you apply
Use a loan calculator to compare the monthly payment and total interest before deciding on a repayment period.
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What a SIP calculator can and cannot tell you
Use return assumptions to plan a range of possible outcomes, not a guaranteed investment result.
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BMI explained: a starting point, not a diagnosis
Understand what a BMI calculation measures, where it is useful, and when to seek personalised medical advice.
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Age on a cut-off date: check eligibility carefully
A practical way to use an age calculator for forms, admissions, exams, and other date-based requirements.
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