ElektroBox Tool
Conversion Calculator for Electronics, Engineering and Maker Projects
Use this browser-based conversion calculator for common engineering and workshop conversions: energy, length, number bases, power, temperature, mass, frequency, area, volume, speed, pressure and digital data units.
Energy conversion
Convert energy units such as joule, watt-hour, calorie and electronvolt.
Length conversion
Convert metric and imperial length units for mechanical dimensions and layouts.
Number conversion
Convert integer values between binary, decimal and hexadecimal.
Power conversion
Convert electrical and mechanical power units.
Temperature conversion
Convert between °C, °F and K using the correct offset calculation.
Mass / weight conversion
Convert common mass units used in datasheets, shipping and workshop notes.
Frequency conversion
Convert hertz, kilohertz, megahertz, gigahertz and rpm.
Area conversion
Convert area units for drawings, layouts and surface calculations.
Volume conversion
Convert volume units for enclosures, fluids and material calculations.
Speed conversion
Convert motion and airflow speed units.
Pressure conversion
Convert pressure units for sensors, pneumatics and lab measurements.
Digital data conversion
Convert bits, bytes and SI/binary storage units.
Best for
- Electronics calculations and datasheet checks
- Arduino, ESP32 and embedded projects
- Workshop documentation and lab notes
- Quick unit checks while building or coding
Before using a result
Check the selected unit, decimal separator and required precision before transferring a result into a real circuit, code constant, BOM or test report.
How to use it
Convert values without leaving the project workflow
Choose a conversion category, enter the known value and select the source and target units. The result updates directly in the browser. The converter accepts both decimal point and decimal comma, which is useful when working with European datasheets or copied spreadsheet values.
Unit conversions
Convert physical quantities such as length, power, energy, frequency, speed, pressure, area and volume.
Number bases
Convert between binary, decimal and hexadecimal for firmware, registers, bitmasks and documentation.
Temperature
Convert between °C, °F and kelvin using the correct offset-based calculation instead of a simple factor.
Examples
Typical project conversions
1 Wh = 3600 JUseful when comparing battery capacity, heating energy or power consumption over time.
6000 rpm = 100 HzUseful for motor speed, rotating systems, sensor pulses and measurement logging.
255 = FF = 11111111Useful for 8-bit limits, register values, masks and protocol debugging.
1 bar = 100000 PaUseful for pneumatic systems, sensor datasheets and lab measurements.
Supported conversions
Conversion categories included
| Category | Common use | Example units |
|---|---|---|
| Energy | Battery, heat and work calculations | J, kJ, Wh, kWh, cal, kcal, eV |
| Length | Mechanical dimensions and layout checks | mm, cm, m, km, in, ft, yd, mi |
| Power | Electrical and mechanical power comparison | W, kW, MW, hp, PS, BTU/h |
| Temperature | Lab conditions and thermal design | °C, °F, K |
| Number bases | Firmware, registers and digital logic | Binary, decimal, hexadecimal |
| Additional units | Engineering documentation and sensor checks | Area, volume, speed, pressure, data |
FAQ
Conversion calculator questions
Does the converter send my values to a server?
No. The conversions run locally in the browser through this plugin’s JavaScript.
Can I use decimal comma?
Yes. Values such as 1,5 are interpreted as 1.5. Large numbers copied with thousands separators are also handled in common European and English formats.
Why is temperature handled separately?
Temperature conversion uses offsets, for example between Celsius and Fahrenheit. It cannot be treated like a simple unit factor conversion.
Is “weight” the same as mass here?
The calculator converts common mass units such as gram, kilogram, tonne, ounce and pound. In everyday language these are often called weight units.