Calculators and timers
Nine tools to calculate, convert and manage your time: loan and BMI calculators, unit conversion, age calculation, sleep cycles, Pomodoro and countdown timers, time zone conversion and meeting planning across countries.
| Tool | Category | Processing |
|---|---|---|
| Loan calculatorMonthly payment, interest and schedule. | Calculators & Time | In your browser |
| BMI calculatorBody mass index and healthy weight. | Calculators & Time | In your browser |
| Unit converterLength, weight, temperature, volume… | Calculators & Time | In your browser |
| Age calculatorExact age, days lived and sign. | Calculators & Time | In your browser |
| Pomodoro timerFocus sessions and breaks. | Calculators & Time | In your browser |
| Countdown timerMultiple color-coded countdowns. | Calculators & Time | In your browser |
| Time zone converterWorld time, live. | Calculators & Time | In your browser |
| Sleep calculatorBedtimes based on sleep cycles. | Calculators & Time | In your browser |
| International meeting plannerShared time slots across countries. | Calculators & Time | In your browser |
About these tools
The calculators answer everyday questions that need a formula: what is the monthly payment on this loan, what is my BMI, how many inches in 30 cm, how old will I be on that date, when should I go to bed to get up at 6? Each result is explained, with the formula used.
The time tools help you get organized: the Pomodoro timer paces your work sessions, countdowns track your kitchen timers as well as your next holiday, and the time zone tools tell you the time elsewhere and find the slot that works for a team spread across several countries.
Everything is calculated in your browser, with no account. Your settings, cities and countdowns are kept in your device's local storage and are not sent anywhere.
Which tool should I use?
Money and health
The “Loan calculator” gives the monthly payment and cost of a loan; the “BMI calculator” places your weight on the WHO scale.
Converting and counting
The “Unit converter” covers 9 quantities; the “Age calculator” gives an exact age and the days between two dates.
Managing your time
The “Pomodoro timer” alternates work and breaks; the “Countdown timer” runs several timers or tracks a date; the “Sleep calculator” finds the best bedtime.
Working across borders
The “Time zone converter” gives the time around the world; the “Meeting planner” finds slots shared by several countries.
Frequently asked questions
Are these calculators reliable?
They use official formulas and definitions (WHO, SI units, IANA time zone database) and are checked by automated tests. For a loan, your lender's offer is what counts.
Is my data sent anywhere?
No. Calculations run in your browser; only your settings are remembered on this device.
Do the timers work in the background?
Yes, they stay accurate. Keep the tab open to hear the alarm.