Calculators & converters

• Convert units

  Length, weight, temperature, volume, speed, area, pressure, energy, data and more. CalculatorsOpen

• Work out a percentage

  Percent of a number, percentage change, increase or decrease by a percent, and more. CalculatorsOpen

• Count days between dates

  Days, weeks, months and business days between two dates, or a date plus or minus some time. CalculatorsOpen

• Add up hours and minutes

  Add up times, convert hours and minutes to decimal hours, and count hours between two times. CalculatorsOpen

• Convert between time zones

  See one moment in several time zones, with daylight saving time worked out. CalculatorsOpen

• Convert Roman numerals

  Numbers to Roman numerals and back, with how each numeral is built. CalculatorsOpen

• Convert binary, hex and decimal

  Binary, octal, decimal, hexadecimal and any base from 2 to 36, with two's complement. CalculatorsOpen

• Pick a random number

  Random numbers in a range, without repeats if you like, or random picks from a list. CalculatorsOpen

• Work out a loan payment

  Monthly payment, total interest and a full payment schedule for any loan, with extra payments. CalculatorsOpen

• Add or remove GST

  Add GST to a price or take it out of a total, with CGST, SGST and IGST shown separately. CalculatorsOpen

• Work out a sale price

  The price after a discount (or two), what you save, and how big a discount really is. CalculatorsOpen

• Work out profit margin and markup

  Margin and markup from cost and price, or the selling price for the margin you want. CalculatorsOpen

• See how savings grow

  How money grows with compound interest and monthly additions, year by year. CalculatorsOpen

• Work out an exact age

  Exact age in years, months and days, totals in weeks and days, and the next birthday. CalculatorsOpen

• Work out your BMI

  Body mass index for adults in kg and cm or pounds, feet and inches, with the healthy weight range. CalculatorsOpen

• Work out a yearly growth rate (CAGR)

  The compound annual growth rate between two values, the end value at a rate, or the years to reach a target. CalculatorsOpen

• Work out return on investment (ROI)

  Return on investment as a percentage, the gain or loss, and the yearly (annualized) return. CalculatorsOpen

• Convert salary to hourly pay

  Turn a yearly, monthly, weekly, daily or hourly pay into all the others, for your working hours. CalculatorsOpen

• Work out the area of a shape

  The area of rectangles, circles, triangles and more, in square feet, square metres, acres, gaj, cents and other units. CalculatorsOpen

• Work out the volume of a shape

  The volume of boxes, cylinders, spheres, cones and more, in litres, cubic metres, cubic feet and gallons. CalculatorsOpen

• Use a scientific calculator

  Trigonometry, logarithms, powers, roots and factorials, typed or tapped, with a history. CalculatorsOpen

• Find the mean, median and more

  Mean, median, mode, range, standard deviation, variance and quartiles of a list of numbers. CalculatorsOpen

• Write a number in words

  Numbers and amounts in words for cheques and invoices, in millions or in lakhs and crores. CalculatorsOpen

• Spin a wheel to pick at random

  A wheel of names: spin it to pick fairly from your list, and take winners off as you go. CalculatorsOpen

Quick conversions

One-click versions of the converters with the format already chosen.

• Calculate a loan EMI
• Calculate a mortgage payment
• Add or remove VAT
• Price with a markup
• Calculate SIP returns
• Calculate standard deviation
• Pick at random from a list

About these tools

Every calculation runs in your browser as you type, and nothing you enter is sent anywhere. Time zones and daylight saving time come from your browser's own time-zone data, and random numbers from its cryptographic random generator.

Money calculators round to cents (or paise) the way bills and statements do, and loan schedules always add up exactly to the amount borrowed. For media maths, see also the Aspect Ratio, Bitrate and Timecode calculators, the DPI & Print Size Calculator and the File Size Converter.

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