Qalculators

31 calculators

Date, time, and conversion tools

Conversion and date tools handle units, time zones, and one-off calculations that do not fit a single industry. Use them as a fast reference layer next to the more specialized clusters.

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01

Tip Calculator

Calculate tip amount and total bill including tip

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02

Age Calculator

Calculate your exact age in years, months, and days

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03

Date Calculator

Calculate the difference between two dates in days, weeks, months, and years

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04

Discount Calculator

Calculate discount amount and final price after discount

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05

Temperature Converter

Convert between Celsius, Fahrenheit, and Kelvin

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06

Length Converter

Convert between different length units (meters, kilometers, inches, feet, etc.)

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07

Weight Converter

Convert between different weight units (kilograms, pounds, ounces, etc.)

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08

Days Between Dates Calculator

Calculate the number of days, weeks, months, and years between two dates

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09

Add Days to Date Calculator

Add or subtract days from a date

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10

Volume Converter

Convert between different volume units (liters, gallons, cups, etc.)

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11

Area Converter

Convert between different area units (square meters, acres, hectares, etc.)

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12

Speed Converter

Convert between different speed units (km/h, mph, m/s, knots)

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13

Time Calculator

Add or subtract time (hours, minutes, seconds)

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14

Random Number Generator

Generate random numbers within a specified range

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15

Number to Words Converter

Convert numbers to words in English

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16

Time Converter

Convert between different time units (seconds, minutes, hours, days, weeks, months, years)

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17

Energy Converter

Convert between different energy units (joules, calories, kilowatt-hours, BTU, etc.)

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18

Power Converter

Convert between different power units (watts, kilowatts, horsepower, BTU/hour)

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19

Pressure Converter

Convert between different pressure units (pascal, bar, psi, atm, torr)

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20

Days Until Date Calculator

Calculate the number of days until a specific date

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21

Week Number Calculator

Calculate the week number of the year for a given date

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22

Days Since Date Calculator

Calculate how many days have passed since a specific date

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23

Roman Numeral Converter

Convert numbers to Roman numerals and vice versa

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24

Base Converter

Convert numbers between different number bases (binary, octal, decimal, hexadecimal)

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25

EV Charging Time Calculator

Calculate electric vehicle charging time based on battery capacity and charging power

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26

Tire Size Comparison Calculator

Compare tire sizes and calculate speedometer error

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27

Horsepower to Torque Converter

Convert between horsepower and torque

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28

Wind Chill Calculator

Calculate the wind chill temperature based on air temperature and wind speed

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29

Heat Index Calculator

Calculate the heat index (feels-like temperature) based on temperature and humidity

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30

Dew Point Calculator

Calculate the dew point temperature based on air temperature and humidity

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31

Bortle Scale Calculator

Estimate light pollution and star visibility using the Bortle Scale

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