Bright Side Kit

CATEGORY

Health Calculators

The math your body runs on: sleep timing in whole 90-minute cycles, daily calorie targets from the Mifflin-St Jeor equation, and more body-math tools — with the formulas shown, not hidden.

Now live: the Sleep Cycle Calculator — bedtimes and wake-up times from whole 90-minute sleep cycles, with a fall-asleep buffer and the 5-cycle sweet spot highlighted — and the new TDEE & Daily Calorie Calculator, which estimates your resting burn with Mifflin-St Jeor, scales it by activity level, and sets calorie and macro targets for losing, maintaining, or gaining. More body-math tools are on the way. Meanwhile, these calculators are ready now:

Health

Sleep cycles

Bedtimes and wake-up times from 90-minute sleep cycles — wake at the end of a cycle, not mid-deep-sleep.

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TDEE & daily calories

Your daily calorie target from the Mifflin-St Jeor equation — BMR, activity-level TDEE, and macros for your goal.

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Other categories

Percentage CalculatorsThe core toolkit: every percentage calculation people actually need.Money CalculatorsEveryday money math — what you pay, what you save, and what you earn.Everyday & Kitchen CalculatorsKitchen conversions, recipe scaling, and unit converters.Time & Date CalculatorsExact age, countdowns, business days, and more.