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work out today?

Solve any percentage question — what is X% of Y, X is what percent of Y, X is Y% of what, and percentage increases or decreases.

Calculate body mass index in metric or imperial units — WHO categories for adults, or CDC growth-chart percentiles for children and teens aged 2–19.

Find your exact age in years, months and days — plus your age in weeks, hours, minutes and seconds, and how long until your next birthday.

Convert between kilometres per hour, miles per hour, metres per second, knots and mach.

Solve a right triangle from any two known parts using the Pythagorean theorem and trigonometry, with all sides, angles and trig ratios.

Convert between standard decimal numbers, scientific notation, engineering notation and E-notation, or do arithmetic directly on two numbers in scientific notation.

Find the slope between two points along with the line equation in every standard form, the angle, and the perpendicular slope.

Calculate what a certificate of deposit is worth at maturity, and what an early withdrawal penalty would cost you.

Calculate your required minimum distribution from a traditional 401(k) or IRA using the IRS Uniform Lifetime Table.

Calculate sales commission from a flat rate or a tiered structure, with accelerators, caps and draws — and both the marginal and retroactive readings of the same tiers.

Estimate body fat percentage from tape measurements using the US Navy method, with lean mass and category comparison.

Calculate the heat index — how hot it feels once humidity is accounted for — with the official NWS regression and risk categories.