BrainyCalc Docs — Unit Conversions

API Reference

Unit Conversions

80+ conversion tools spanning every major physical quantity. All converters share a common interface: value, fromUnit, toUnit. Results are accurate to 10 significant figures.

Common interface

Every conversion tool takes the same three parameters. The tool name identifies the dimension — e.g. convert_length, convert_mass, convert_temperature.

convert_* — shared parameters

All conversion tools share this exact input schema.

all converters

Parameter	Type	Required	Description
`value`	number	required	The numeric value to convert
`fromUnit`	string	required	Unit string to convert from (see unit lists below)
`toUnit`	string	required	Unit string to convert to

Response shape (all converters)

{
  "value": 1,
  "fromUnit": "mile",
  "toUnit": "km",
  "convertedValue": 1.609344
}

Everyday

convert_length

26 units from picometers to parsecs

mkmcmmmumnmpmfminchfootyardmilenautical_mileleaguelight_yearastronomical_unitparsecangstromchainfurlonghandrodfathomcubitellspan

convert_mass

16 units from nanograms to metric tons

kggmgugngmetric_tonshort_tonlong_tonlbozstonegraincaratdramtroy_oztroy_lb

convert_volume

22 units including US/UK variants

litermlcldlcubic_mcubic_cmcubic_ftcubic_ingallon_usgallon_ukquart_uspint_uscup_usfl_oz_ustablespoon_usteaspoon_usbarrel_oilbarrel_us

convert_temperature

Non-linear conversion using dedicated formulas

CFKRDeNReRo

Temperature example

{ "value": 100, "fromUnit": "C", "toUnit": "F" }
→ { "convertedValue": 212 }

convert_speed

9 units

m/skm/hmphknotft/smi/mincm/sMachlight_speed

convert_area

16 units including land area

m2km2cm2mm2inch2foot2yard2mile2acrehectareare

convert_time

11 units from nanoseconds to centuries

nsusmssminhourdayweekmonthyeardecadecentury

Electrical

Tool	Description	Example units
`convert_voltage`	Electric potential	V, mV, kV, MV
`convert_current`	Electric current	A, mA, uA, kA
`convert_resistance`	Electrical resistance	ohm, milliohm, kilohm, megaohm
`convert_capacitance`	Electric capacitance	F, mF, uF, nF, pF
`convert_inductance`	Electrical inductance	H, mH, uH, nH
`convert_charge`	Electric charge	C, mC, uC, nC, pC
`convert_conductance`	Electrical conductance	S, mS, uS, nS
`convert_resistivity`	Electrical resistivity	ohm_m, ohm_cm, ohm_mm2/m
`convert_electric_field`	Electric field strength	V/m, kV/m, MV/m, V/cm

Mechanics

Tool	Description	Example units
`convert_force`	Mechanical force	N, kN, dyn, lbf, kgf
`convert_pressure`	Pressure	Pa, kPa, MPa, bar, atm, psi, torr
`convert_energy`	Energy / work	J, kJ, MJ, kWh, cal, kcal, BTU, eV
`convert_power`	Power	W, kW, MW, hp, BTU/h
`convert_torque`	Torque	N·m, kN·m, lbf·ft, lbf·in, kgf·m
`convert_acceleration`	Acceleration	m/s2, g, ft/s2, cm/s2
`convert_momentum`	Linear momentum	kg·m/s, g·cm/s, lb·ft/s
`convert_density`	Mass density	kg/m3, g/cm3, g/L, lb/ft3
`convert_flow_rate`	Volumetric flow	m3/s, L/s, L/min, ft3/s, gal/min

Thermodynamics

Tool	Description	Example units
`convert_heat_flux`	Heat flux density	W/m2, kW/m2, BTU/h·ft2
`convert_thermal_conductivity`	Thermal conductivity	W/m·K, BTU/h·ft·°F, cal/s·cm·°C
`convert_specific_heat`	Specific heat capacity	J/kg·K, kJ/kg·K, cal/g·°C, BTU/lb·°F
`convert_thermal_expansion`	Coefficient of thermal expansion	1/K, 1/°C, 1/°F, 1/°R

Optics & Radiation

Tool	Description	Example units
`convert_illuminance`	Light intensity on a surface	lux, fc, phot, nox
`convert_luminance`	Light emitted per area	cd/m2, nit, stilb, apostilb, fL
`convert_luminous_intensity`	Luminous intensity	cd, mcd, kcd
`convert_frequency_wavelength`	Frequency ↔ wavelength (em radiation)	Hz, kHz, MHz, GHz, THz, nm, um, mm, cm, m
`convert_radiation_dose`	Absorbed radiation dose	Gy, mGy, rad, uGy
`convert_radiation_exposure`	Radiation exposure	C/kg, R, mR, uR

Data

Tool	Description	Example units
`convert_data_storage`	Digital storage	bit, byte, KB, MB, GB, TB, PB, KiB, MiB, GiB, TiB
`convert_data_transfer`	Data transfer rate	bps, Kbps, Mbps, Gbps, Tbps, KBps, MBps, GBps
`convert_image_resolution`	Image resolution	dpi, ppi, dpcm, ppcm

Data storage example

{ "value": 1, "fromUnit": "GB", "toUnit": "bit" }
→ { "convertedValue": 8000000000 }

Chemistry

Tool	Description	Example units
`convert_molar_concentration`	Molar concentration	mol/L, mmol/L, umol/L, nmol/L, mol/m3, mol/cm3
`convert_solution_concentration`	Mass concentration	g/L, mg/L, ug/L, g/dL, g/mL, ppm, ppb
`convert_dynamic_viscosity`	Dynamic viscosity	Pa·s, mPa·s, cP, P, lb/ft·s
`convert_kinematic_viscosity`	Kinematic viscosity	m2/s, cm2/s, mm2/s, cSt, St, ft2/s

Engineering

Tool	Description	Example units
`convert_angular_velocity`	Rotational speed	rad/s, deg/s, rpm, rps, grad/s
`convert_angular_acceleration`	Change in angular velocity	rad/s2, deg/s2, rpm/s, rps/s
`convert_moment_of_inertia`	Rotational inertia	kg·m2, g·cm2, lb·ft2, lb·in2
`convert_surface_tension`	Surface tension	N/m, mN/m, dyn/cm, lbf/in, lbf/ft

Specialist

Tool	Description	Example units
`convert_typography`	Typographic units	pt, px, em, rem, pc, cm, mm, inch, twip
`convert_number_base`	Number base conversion	decimal ↔ binary ↔ octal ↔ hexadecimal
`convert_si_prefix`	SI prefix scaling	base, kilo, mega, giga, tera, peta, milli, micro, nano, pico

Number base example

{ "value": 255, "fromUnit": "decimal", "toUnit": "hexadecimal" }
→ { "convertedValue": "ff" }