Unit, date and time converters

Conversions are reliable only when the input and output units are clear. These tools cover measurements such as length, area, volume, weight, temperature, pressure and data storage, alongside dates and time zones. Enter a value, choose the source unit and select the result you need. For example, a temperature conversion needs both a scale change and an offset: 0 degrees Celsius is 32 degrees Fahrenheit. Simply multiplying by a ratio would give the wrong answer.

Watch for units with similar names. US and imperial volume measures differ, and decimal storage units such as megabytes differ from binary units such as mebibytes. A rounded display can be useful for a recipe or a quick estimate, but retain enough precision when a result will feed another calculation. The individual converter lists the units and conventions it supports.

Date and time tasks need a little more context. A time-zone offset can change with daylight saving time, so use a date as well as a location when planning a meeting. Calendar days are different from working days, and an inclusive date interval is different from elapsed days. Choose the tool that matches your convention and check the displayed assumptions before copying a result into a schedule.

Browse 28 tools

Converters tools

BTU to kW ConverterConvert BTU to kW for heating and cooling capacity. Enter BTU/h and get kilowatts, watts and refrigeration tons instantly in your browser.Data Storage ConverterConvert data storage units instantly between bits, bytes, KB, MB, GB, TB and IEC units such as KiB, MiB and GiB. Free and private in your browser.PPI CalculatorPPI calculator for screens and images. Enter resolution and diagonal size to find pixel density, pixel pitch, megapixels and physical dimensions.Area ConverterFree area converter for square meters, square feet, acres, hectares and other metric or imperial units. See every conversion instantly.Energy ConverterConvert energy units instantly between joules, kWh, calories, BTU, therms and electronvolts, with exact factors and an all-units table.Temperature ConverterFree temperature converter for Celsius, Fahrenheit and Kelvin. Type a value and get all three scales at once, with the formula shown - instant, no sign-up, runs in your browser.Length ConverterFree length and distance converter. Enter a value and convert instantly between millimeters, centimeters, meters, kilometers, inches, feet, yards, miles and more - runs in your browser.Meters to Feet ConverterFree meters to feet converter. Type a length in meters and get feet, plus the exact feet and inches - instant, no sign-up, runs in your browser.Pressure ConverterFree pressure converter for PSI, bar, Pa, kPa, MPa, atm, Torr, mmHg and more. Convert live with an all-units table in your browser.Speed ConverterFree speed and velocity converter. Enter a value and convert instantly between km/h, mph, m/s, feet per second, knots and Mach - runs in your browser, nothing uploaded.Volume ConverterFree volume converter for liters, milliliters, gallons, cups, fluid ounces, cubic meters, cubic inches and cubic feet. Runs in your browser.Weight ConverterFree weight converter for kilograms, pounds, ounces, stones, grams and tons. Get exact live results and mixed formats in your browser.Age CalculatorFree age calculator: enter a date of birth to get your exact age in years, months and days, plus age in weeks, days, hours - and your next birthday.Business Days CalculatorFree business days calculator. Count the working days between two dates, skip weekends, and exclude your own public holidays. Runs in your browser.Calendar GeneratorFree calendar generator for any month and year. Choose Sunday or Monday starts, add notes and week numbers, then print a clean calendar in your browser.Countdown TimerFree online countdown timer with alarm. Set any duration in minutes or hours, then start, pause and reset. Runs in your browser - no sign-up, no download.Date CalculatorFree date calculator to add or subtract days, weeks, months and years from any date. Instant, private and accurate for month-end dates.Day of Week FinderFind the day of the week for any past or future date. See its ISO week, day of year, month occurrence, and leap-year status instantly.ISO Date ConverterConvert and validate ISO 8601 dates in your browser. Normalize offsets to UTC, inspect date parts, and copy local, UTC, or Unix values instantly.Days Between Dates CalculatorFree days between dates calculator. Count the exact number of days between two dates, with a years, months, and days breakdown and an include-end-date option. Runs in your browser.Meeting Time PlannerMeeting time planner for finding shared working hours across time zones. Compare up to six people with DST-aware local times. No sign-up.Pomodoro TimerFree online Pomodoro timer with 25-minute focus sessions, short and long breaks, custom intervals, alarms, and daily progress saved in your browser.Recurring Date CalculatorRecurring date calculator to generate daily, weekly, monthly or yearly schedules. Handle month ends, list up to 200 dates and copy the results.Time Between Two Times CalculatorFree calculator for the time between two times. Enter a start and end time to get the hours and minutes between them - overnight spans handled, all in your browser.Time Duration CalculatorCalculate the exact time duration between two dates and times in days, hours, minutes and seconds. Handles overnight and multi-day ranges in your browser.Time Zone ConverterFree time zone converter for meetings, calls and travel. Compare cities instantly with DST-aware offsets. No sign-up or upload.Unix Timestamp ConverterConvert Unix timestamps to human-readable dates and back, free in your browser. Auto-detects seconds vs milliseconds and shows UTC, local time and ISO 8601.Working Hours CalculatorWorking hours calculator for weekly shifts, unpaid breaks, overnight work and decimal totals. Add up to 14 shifts privately in your browser.