18 Free and Open-source Unit Converters for Windows, Linux, macOS, Android and iOS

[ad_1]

A unit converter app is a software application that allows users to convert values from one unit of measurement to another. It provides a convenient and efficient way to perform conversions between various physical quantities such as length, area, volume, mass, time, temperature, energy, and more.

Unit converter apps typically offer a user-friendly interface, allowing users to input a value in one unit and get the equivalent value in another unit instantly. They can be used for a wide range of purposes, including education, engineering, cooking, and everyday life.

In this blog post, we will introduce you to 18 amazing unit converter apps that can be used across various platforms. Whether you’re using Windows, Linux, macOS, Android, or iOS, there’s a unit converter tailored for your needs.

These unit converters offer a wide range of features, including support for conversions in different physical quantities such as length, area, volume, mass, time, temperature, energy, and more. Some of them even come with additional functionalities like currency exchange rate conversions, date calculations, scientific calculations, and custom conversions.

1- Converter NOW

Converter NOW is an easy, fast, and customizable unit converter app with a built-in calculator, daily updated currency exchange rates, dynamic theming, and multiplatform availability.

It is free, ad-free, does not collect data, and is open source.

2- Unit Converter – Windows OS Application for unit conversions

Unit Converter is a Windows OS Application that allows for easy conversions between various physical quantities such as length, area, volume, mass, time, temperature, energy, frequency, pressure, speed, plane angle, fuel economy, data transfer rate, and data storage.

3- Pebbles

Pebbles is an advanced calculator application based in Vala and Gtk.

4- Convert

Convert for Windows is a free and user-friendly unit conversion program that supports a wide range of units, including distance, temperature, volume, time, speed, mass, power, density, pressure, energy, and more. It also allows users to create custom conversions.

5- Converter

Converter is a customizable unit converter application built on wxWidgets. It is licensed under the MIT license and can be compiled and run under both MSW and GTK.

6- Unito

Unito is a Flutter app that demonstrates modern materialistic UI with features like dynamic theme, animated splash screen, Flare 2D animations, and transition animations.

7- Calculator

Calculator is a remarkable open-source app that combines simplicity and elegance. It is built with Flutter, utilizing Google’s Material Design principles. The app includes features such as Currency (Exchange Rate) and Unit Converter, making it versatile and practical.

Platforms: Mobile: Android

8- CalculatorApp

CalculatorApp is a powerful Android application that seamlessly combines the functionality of a basic calculator, scientific calculator, and unit converter.

9- Multi-Calculator

Multi-Calculator is a free and open-source feature-rich calculator for Android.

Primary Features

Fancy open-source calculator for Android
Includes unit converter, date calculator, and BMI calculator
Lightweight (<5MB)
No unnecessary permissions required
Material Design 3
History feature
Supports portrait and landscape orientation
Multiple useful functions
Calculator:
- Basic arithmetic operations (addition, subtraction, multiplication, division)
- Advanced calculations (power, square root, factorial, double factorial, percentage)
- Support for scientific calculations (logarithm, trigonometric functions)
- Input of scientific constants (e, π)
- Real-time display of calculation results and historical record function
Unit Converter:
- Support for various unit conversions (length, area, volume, mass, temperature, storage, pressure, etc.)
- Quick and convenient conversion between different units
Date Calculator:
- Calculation of date intervals
- Calculation of future or past dates based on a specified date and number of days
Compass:
- Obtain information such as azimuth, magnetic declination, latitude and longitude, altitude, speed, magnetic field, address, atmospheric pressure
BMI Calculator:
- Calculation of BMI index based on height and weight
- Provision of health advice based on the calculation results
Live Currency Exchange Rate Converter:
- Support for multiple currency types
- Accurate currency exchange rate conversions based on real-time data
Uppercase Chinese Digit Converter:
- Conversion of Arabic numerals to uppercase Chinese numerals
Relative Salutation Calculator:
- Calculation of Chinese titles by kinship
- Determination of correct Chinese address based on specified relationship
Financial Calculator:
- Calculation of bank deposits, investment returns, loans, and VAT
- Data visualization through charts
Random Number Function:
- Generation of random numbers within a specified range
Equation Solving Function:
- Solving of linear equations and quadratic equations in one variable
Shopping Assistant:
- Quick calculation of discounts and unit prices
Mathematical Statistics:
- Calculation of common statistical values (greatest common divisor, least common multiple, arithmetic mean, geometric mean, harmonic mean, square mean, variance, standard deviation, sum)

Toolz is a Unit Converter app inspired from the Architecture of Windows 11 Calculator’s Converter Section & built to Demonstrate use of Jetpack Compose with Modern Android Architecture Components & MVVM Architecture.

Features

Here are the simple features of the Toolz Unit Converter:

Volume conversions between liter, milliliter, gallon (US), gallon (UK), quart (US), quart (UK), pint (US), pint (UK), cup (US), cup (UK), fluid ounce (US), fluid ounce (UK), tablespoon (US), tablespoon (UK), teaspoon (US), and teaspoon (UK).
Temperature conversions between Celsius, Fahrenheit, and Kelvin.
Weight conversions between kilogram, gram, milligram, pound, ounce, and stone.
Length conversions between kilometer, meter, centimeter, millimeter, mile, yard, foot, and inch.
Time conversions between year, month, week, day, hour, minute, and second.
Speed conversions between kilometer per hour, meter per second, mile per hour, and knot.

Download

11- D&D Unit Converter

D&D Unit Converter is a tool that allows for easy conversion between different units used in the Dungeons and Dragons universe, including currencies, weights, volumes, and more.

11- Engineering Calculator and Unit Converter

The Engineering Calculator is a convenient tool for math expression evaluation and unit conversion. Recent updates include new display modes for “feet & inches” and “deg, min, sec”, the option to use a comma-based decimal point, and the ability to adjust the number of significant figures. Version 1.6 also introduced bit-wise logical operators.

12- CalcConv

CalcConv is a Command-Line Calculator with additional functionalities, developed as part of a mini project for Object Oriented Programming Using C++. It consists of 4 modules: Basic Module, Quadratic Equation Solver, Unit Converter, and Logging.

13- Tauri Unit Converter

Tauri Unit Converter is a desktop application built with Tauri, using a rust backend and SolidJS frontend. It converts units by first converting the “from” unit to a base unit, then converting that number to the “to” unit. Tauri is a cross-platform desktop application toolkit that replaces the NodeJS backend with rust and the chromium frontend with WebView.

14- NumericalChameleon

The NumericalChameleon is a free, open source unit converter for macOS, Linux, and Windows desktop.

15- Unit Converter

Unit Converter is an iOS mobile application built with SwiftUI and MVVM design pattern. It provides accurate conversions for various units using Swift Measurement Unit Conversion API, offering a seamless user experience and efficient code organization.

16- Qalculate

Qalculate! is a powerful and versatile desktop calculator that offers a wide range of features, including customizable functions, unit conversion, symbolic calculations, plotting, and a user-friendly interface. It is free software licensed under the GNU Public License v2 or later.

Features

Here are the simple features of Qalculate!:

Customizable functions
Unit conversion
Symbolic calculations
Plotting
User-friendly interface
Large library of customizable functions
Physical constants
Arbitrary precision
Uncertainty propagation
Interval arithmetic
Cross-platform availability (GTK, Qt, CLI)

17- Trevor

Trevor is an open-source Electron based unit converter app inspired by Numi and powered by React.

18- Unit Converter Ultimate

Unit Converter Ultimate is a lightweight, Material Design themed unit converter for Android, designed for quick and easy conversions without overwhelming options and settings. Ideal for work, school, or in the kitchen.

Available unit conversions

Currency (US dollar, CDN dollar, pound, peso, etc)
Temperature (celsius, fahrenheit, kelvin, etc)
Length (kilometer, miles, meter, yard, feet, etc)
Mass/Weight (kilogram, pound, ounce, ton, stone, etc)
Speed (km/h, mph, knot, etc)
Area (square kilometer, square mile, hectare, acre, etc)
Cooking (teaspoon, tablespoon, cup, pint, quart, ounce, etc)
Volume (cubic metres, cubic inches, litres, gallons, etc)
Pressure (kilopascal, bar, PSI, etc)
Power (watt, kilowatt, horsepower, etc)
Energy (joule, calorie, BTU, etc)
Time (year, month, day, hour, second, etc)
Fuel Consumption (miles per gallon, liters per 100km, etc)
Digital Storage (bit, byte, megabytes, gigabytes, etc)