List of default units

List of default units#

The default definitions can be found at default_en.txt and have been used to generate the following lists.

Hover over the name of a unit to see its value.

Prefixes#

  • atto (a)

  • centi (c)

  • deca (da) – deka

  • deci (d)

  • exa (E)

  • exbi (Ei)

  • femto (f)

  • gibi (Gi)

  • giga (G)

  • hecto (h)

  • kibi (Ki)

  • kilo (k)

  • mebi (Mi)

  • mega (M)

  • micro (μ) – µ, u, mu, mc

  • milli (m)

  • nano (n)

  • pebi (Pi)

  • peta (P)

  • pico (p)

  • quecto (q)

  • quetta (Q)

  • ronna (R)

  • ronto (r)

  • semi – demi

  • sesqui

  • tebi (Ti)

  • tera (T)

  • yobi (Yi)

  • yocto (y)

  • yotta (Y)

  • zebi (Zi)

  • zepto (z)

  • zetta (Z)

Units#

  • LMH

  • RKM

  • UK_force_ton – UK_ton_force

  • UK_hundredweight (UK_cwt)

  • UK_ton

  • US_force_ton – US_ton_force

  • US_hundredweight (US_cwt)

  • US_international_ampere (A_US)

  • US_international_ohm (Ω_US) – ohm_US

  • US_international_volt (V_US)

  • US_therm

  • US_ton

  • abampere (abA)

  • abcoulomb (abC)

  • aberdeen (Ta)

  • abfarad (abF)

  • abhenry (abH)

  • abohm (abΩ)

  • absiemens (abS) – abmho

  • absorbance_unit (AU)

  • abvolt (abV)

  • acre

  • acre_foot – acre_feet

  • ampere (A) – amp

  • ampere_hour (Ah)

  • ampere_turn (At)

  • angstrom (Å) – ångström, Å

  • angstrom_star (Å_star)

  • apothecary_dram (ap_dr) – apothecary_drachm, drachm

  • apothecary_ounce (ap_oz)

  • apothecary_pound (ap_lb)

  • arcminute (arcmin) – arc_minute, angular_minute

  • arcsecond (arcsec) – arc_second, angular_second

  • are

  • astronomical_unit (au)

  • atmosphere_liter (atm_l)

  • atomic_mass_constant (m_u)

  • atomic_unit_of_current (a_u_current)

  • atomic_unit_of_electric_field (a_u_electric_field)

  • atomic_unit_of_electric_field_gradient (a_u_efg)

  • atomic_unit_of_force (a_u_force)

  • atomic_unit_of_intensity (a_u_intensity)

  • atomic_unit_of_temperature (a_u_temp)

  • atomic_unit_of_time (a_u_time)

  • avogadro_constant (N_A)

  • avogadro_number

  • bag

  • bar

  • barn (b)

  • barrel (bbl)

  • barye (Ba) – barie, barad, barrie, baryd

  • baud (Bd) – bps

  • beats_per_minute (bpm)

  • becquerel (Bq)

  • beer_barrel (beer_bbl)

  • biot (Bi)

  • biot_turn

  • bit

  • bits_per_pixel (bpp)

  • board_foot (FBM) – board_feet, BF, BDFT, super_foot, superficial_foot, super_feet, superficial_feet

  • bohr (a_0) – a0, bohr_radius, atomic_unit_of_length, a_u_length

  • bohr_magneton (µ_B) – mu_B

  • boiler_horsepower

  • boltzmann_constant (k) – k_B

  • british_thermal_unit (Btu) – BTU, Btu_iso

  • buckingham

  • bushel (bu)

  • byte (B) – octet

  • cables_length

  • calorie (cal) – thermochemical_calorie, cal_th

  • candela (cd) – candle

  • carat (ct)

  • centimeter (cm)

  • centipoise (cP)

  • century – centuries

  • chain

  • cicero

  • circular_mil (cmil)

  • classical_electron_radius (r_e)

  • clausius (Cl)

  • common_year

  • conductance_quantum (G_0)

  • conventional_ampere_90 (A_90)

  • conventional_coulomb_90 (C_90)

  • conventional_farad_90 (F_90)

  • conventional_henry_90 (H_90)

  • conventional_josephson_constant (K_J90)

  • conventional_mercury_density (ρHg)

  • conventional_ohm_90 (Ω_90) – ohm_90

  • conventional_volt_90 (V_90)

  • conventional_von_klitzing_constant (R_K90)

  • conventional_water_density (ρH2O)

  • conventional_watt_90 (W_90)

  • cooling_tower_ton

  • coulomb (C)

  • coulomb_constant (k_C)

  • count

  • counts_per_second (cps)

  • css_pixel (px)

  • cubic_centimeter (cc)

  • cubic_foot (cu_ft) – cubic_feet

  • cubic_inch (cu_in)

  • cubic_yard (cu_yd)

  • cup (cp) – liquid_cup, US_liquid_cup

  • curie (Ci)

  • dalton (Da)

  • darcy

  • day (d)

  • debye (D)

  • decade

  • decibel (dB)

  • decibelmicrowatt (dBu)

  • decibelmilliwatt (dBm)

  • decibelwatt (dBW)

  • decimeter (dm)

  • decitex (dTt)

  • degree (deg) – arcdeg, arcdegree, angular_degree

  • degree_Celsius (°C) – celsius, degC, degreeC

  • degree_Fahrenheit (°F) – fahrenheit, degF, degreeF

  • degree_Rankine (°R) – rankine, degR, degreeR

  • degree_Reaumur (°Re) – reaumur, degRe, degreeRe, degree_Réaumur, réaumur

  • delta_degree_Celsius (Δ°C) – Δcelsius, ΔdegC, ΔdegreeC, delta_celsius, delta_degC, delta_degreeC

  • delta_degree_Fahrenheit (Δ°F) – Δfahrenheit, ΔdegF, ΔdegreeF, delta_fahrenheit, delta_degF, delta_degreeF

  • delta_degree_Reaumur (Δ°Re) – Δreaumur, ΔdegRe, ΔdegreeRe, Δdegree_Réaumur, Δréaumur, delta_reaumur, delta_degRe, delta_degreeRe, delta_degree_Réaumur, delta_réaumur

  • denier (den)

  • didot

  • dirac_constant (ħ) – hbar, atomic_unit_of_action, a_u_action

  • dram (dr) – avoirdupois_dram, avdp_dram

  • dry_barrel – US_dry_barrel

  • dry_gallon (dgal) – US_dry_gallon

  • dry_pint (dpi) – US_dry_pint

  • dry_quart (dqt) – US_dry_quart

  • dtex

  • dyne (dyn)

  • electrical_horsepower

  • electron_g_factor (g_e)

  • electron_mass (m_e) – atomic_unit_of_mass, a_u_mass

  • electron_volt (eV) – electronvolt

  • elementary_charge (e)

  • entropy_unit (eu)

  • enzyme_unit (U) – enzymeunit

  • eon

  • erg

  • eulers_number

  • farad (F)

  • faraday

  • faraday_constant

  • fathom

  • femtometer (fm)

  • fermi (fm)

  • fifteen_degree_calorie (cal_15)

  • fifth – US_liquid_fifth

  • fine_structure_constant (α) – alpha

  • first_radiation_constant (c_1)

  • fluid_dram (fldr) – fluidram, US_fluid_dram, US_liquid_dram

  • fluid_ounce (floz) – US_fluid_ounce, US_liquid_ounce

  • foot (ft) – international_foot, feet, international_feet

  • foot_H2O (ftH2O) – ft_H2O, feetH2O, feet_H2O

  • foot_H2O_4C (ftH2O_4C) – ft_H2O_4C, feetH2O_4C, feet_H2O_4C

  • foot_H2O_60F (ftH2O_60F) – ft_H2O_60F, feetH2O_60F, feet_H2O_60F

  • foot_Hg (ftHg) – ft_Hg, feetHg, feet_Hg

  • foot_Hg_0C (ftHg_0C) – ft_Hg_0C, feetHg_0C, feet_Hg_0C

  • foot_Hg_32F (ftHg_32F) – ft_Hg_32F, feetHg_32F, feet_Hg_32F

  • foot_Hg_60F (ftHg_60F) – ft_Hg_60F, feetHg_60F, feet_Hg_60F

  • foot_per_second (fps)

  • foot_pound (ft_lb) – footpound

  • force_gram (gf) – gram_force, pond

  • force_kilogram (kgf) – kilogram_force

  • force_long_ton – long_ton_force

  • force_metric_ton (tf) – metric_ton_force, force_t, t_force

  • force_ounce (ozf) – ounce_force

  • force_pound (lbf) – pound_force

  • force_ton – ton_force, force_short_ton, short_ton_force

  • fortnight

  • franklin (Fr) – statcoulomb, statC, esu

  • furlong (fur)

  • galileo (Gal)

  • gallon (gal) – liquid_gallon, US_liquid_gallon

  • gamma (γ)

  • gamma_mass

  • gauss (G)

  • gilbert (Gb)

  • gill (gi) – liquid_gill, US_liquid_gill

  • grade (grad) – gon, gradian

  • grain (gr)

  • gram (g)

  • gray (Gy)

  • gregorian_year

  • hand

  • hartree (E_h) – Eh, hartree_energy, atomic_unit_of_energy, a_u_energy

  • hectare (ha)

  • henry (H)

  • hertz (Hz)

  • hogshead

  • horsepower (hp) – UK_horsepower, hydraulic_horsepower

  • hour (h) – hr

  • hundredweight (cwt) – short_hundredweight

  • impedance_of_free_space (Z_0) – characteristic_impedance_of_vacuum

  • imperial_barrel (imperial_bbl) – UK_bbl

  • imperial_bushel (imperial_bu) – UK_bushel

  • imperial_cup (imperial_cp) – UK_cup

  • imperial_fluid_drachm (imperial_fldr) – imperial_fluid_dram

  • imperial_fluid_ounce (imperial_floz) – UK_fluid_ounce

  • imperial_fluid_scruple

  • imperial_gallon (imperial_gal) – UK_gallon

  • imperial_gill (imperial_gi) – UK_gill

  • imperial_minim

  • imperial_peck (imperial_pk) – UK_pk

  • imperial_pint (imperial_pt) – UK_pint

  • imperial_quart (imperial_qt) – UK_quart

  • inch (in) – international_inch, inches, international_inches

  • inch_H2O (inH2O) – in_H2O, inchesH2O, inches_H2O

  • inch_H2O_4C (inH2O_4C) – in_H2O_4C, inchesH2O_4C, inches_H2O_4C

  • inch_H2O_60F (inH2O_60F) – in_H2O_60F, inchesH2O_60F, inches_H2O_60F

  • inch_Hg (inHg) – in_Hg, inchesHg, inches_Hg

  • inch_Hg_0C (inHg_0C) – in_Hg_0C, inchesHg_0C, inches_Hg_0C

  • inch_Hg_32F (inHg_32F) – in_Hg_32F, inchesHg_32F, inches_Hg_32F

  • inch_Hg_60F (inHg_60F) – in_Hg_60F, inchesHg_60F, inches_Hg_60F

  • international_british_thermal_unit (Btu_it)

  • international_calorie (cal_it) – international_steam_table_calorie

  • josephson_constant (K_J)

  • joule (J)

  • jute (Tj)

  • katal (kat)

  • kelvin (K) – degK, °K, degree_Kelvin, degreeK

  • kilogram (kg)

  • kilometer (km)

  • kilometer_per_hour (kph) – KPH

  • kilometer_per_second (kps)

  • kip

  • kip_per_square_inch (ksi)

  • knot (kn) – kt, knot_international, international_knot

  • lambda (λ)

  • lambert

  • langley (Ly)

  • league

  • leap_year

  • light_year (ly) – lightyear

  • link (li) – survey_link

  • liter (l) – L, ℓ, litre

  • ln10

  • long_hundredweight

  • long_ton

  • lumen (lm)

  • lux (lx)

  • magnetic_flux_quantum (Φ_0) – Phi_0

  • maxwell (Mx)

  • mean_international_ampere (A_it)

  • mean_international_ohm (Ω_it) – ohm_it

  • mean_international_volt (V_it)

  • mercury_density_0C (ρHg_0C)

  • mercury_density_32F (ρHg_32F)

  • mercury_density_60F (ρHg_60F)

  • meter (m) – metre

  • meter_H2O (mH2O) – m_H2O

  • meter_H2O_4C (mH2O_4C) – m_H2O_4C

  • meter_H2O_60F (mH2O_60F) – m_H2O_60F

  • meter_Hg (mHg) – m_Hg

  • meter_Hg_0C (mHg_0C) – m_Hg_0C

  • meter_Hg_32F (mHg_32F) – m_Hg_32F

  • meter_Hg_60F (mHg_60F) – m_Hg_60F

  • meter_per_second (mps)

  • meter_per_second_squared

  • metric_horsepower

  • metric_ton (t) – tonne

  • microgram (μg)

  • microliter (μl)

  • micrometer (μm)

  • micromole (μmol)

  • micron (μ) – µ

  • mil

  • mile (mi) – international_mile

  • mile_per_hour (mph) – MPH

  • millennium – millennia

  • milliarcsecond (mas)

  • milligram (mg)

  • minim

  • minute (min)

  • molar (M)

  • molar_gas_constant (R)

  • mole (mol)

  • month

  • nautical_mile (nmi)

  • neper (Np)

  • neutron_mass (m_n)

  • newton (N)

  • newtonian_constant_of_gravitation – gravitational_constant

  • nit

  • nuclear_magneton (µ_N) – mu_N

  • number_english (Ne) – NeC, ECC

  • number_meter

  • octave (oct)

  • oersted (Oe) – ørsted

  • ohm (Ω)

  • oil_barrel (oil_bbl)

  • ounce (oz) – avoirdupois_ounce, avdp_ounce

  • parsec (pc)

  • particle – molec, molecule

  • pascal (Pa)

  • peak_sun_hour (PSH)

  • peck (pk)

  • pennyweight (dwt)

  • percent (%)

  • permille (‰)

  • pi (π)

  • pica – printers_pica

  • pint (pt) – liquid_pint, US_pint

  • pixel – dot, pel, picture_element

  • pixels_per_centimeter (PPCM)

  • pixels_per_inch (dots_per_inch) – PPI, ppi, DPI, printers_dpi

  • planck_constant (ℎ)

  • planck_current

  • planck_length

  • planck_mass

  • planck_temperature

  • planck_time

  • point (pp) – printers_point, big_point, bp

  • poise (P)

  • pound (lb) – avoirdupois_pound, avdp_pound

  • pound_force_per_square_inch (psi)

  • poundal (pdl)

  • ppm

  • proton_mass (m_p)

  • quadrillion_Btu (quad)

  • quart (qt) – liquid_quart, US_liquid_quart

  • quarter

  • radian (rad)

  • rads

  • reciprocal_centimeter (cm_1) – kayser

  • refractive_index_unit (RIU)

  • refrigeration_ton – ton_of_refrigeration

  • rem

  • revolutions_per_minute (rpm)

  • revolutions_per_second (rps)

  • reyn

  • rhe

  • rod (rd) – pole, perch

  • roentgen – röntgen

  • rutherford (Rd)

  • rydberg (Ry)

  • rydberg_constant (R_∞) – R_inf

  • scaled_point

  • scruple

  • second (s) – sec

  • second_radiation_constant (c_2)

  • shake

  • shot (jig) – US_shot

  • sidereal_day

  • sidereal_month

  • sidereal_year

  • siemens (S) – mho

  • sievert (Sv)

  • slinch (blob) – slugette

  • slug

  • sound_pressure_level (SPL)

  • speed_of_light (c) – c_0

  • square_degree (sq_deg) – sqdeg

  • square_foot (sq_ft) – square_feet

  • square_inch (sq_in) – square_inches

  • square_league

  • square_mile (sq_mi)

  • square_rod (sq_rod) – sq_pole, sq_perch

  • square_survey_mile – section

  • square_yard (sq_yd)

  • standard_atmosphere (atm) – atmosphere

  • standard_gravity (g_0) – g0, g_n, gravity

  • standard_liter_per_minute (slpm) – slm

  • statampere (statA)

  • statfarad (statF)

  • stathenry (statH)

  • statmho

  • statohm (statΩ)

  • stattesla (statT)

  • statvolt (statV)

  • statweber (statWb)

  • stefan_boltzmann_constant (σ) – sigma

  • steradian (sr)

  • stere

  • stilb

  • stokes (St)

  • stone

  • strain (ε) – ϵ

  • survey_foot (sft)

  • survey_mile (smi) – us_statute_mile

  • svedberg

  • sverdrup (sv)

  • synodic_month – lunar_month

  • tablespoon (tbsp)

  • tansec

  • teaspoon (tsp)

  • technical_atmosphere (at)

  • tesla (T)

  • tex (Tt)

  • tex_cicero

  • tex_didot

  • tex_pica

  • tex_point

  • therm (thm) – EC_therm

  • thermochemical_british_thermal_unit (Btu_th)

  • thomson_cross_section (σ_e) – sigma_e

  • thou (th) – mil_length

  • ton – short_ton

  • ton_TNT (tTNT)

  • tonne_of_oil_equivalent (toe)

  • torr

  • townsend (Td)

  • tropical_month

  • tropical_year

  • troy_ounce (toz) – ozt

  • troy_pound (tlb) – lbt

  • turn – revolution, cycle, circle

  • unified_atomic_mass_unit (u) – amu

  • unit_pole

  • vacuum_permeability (µ_0) – mu_0, mu0, magnetic_constant

  • vacuum_permittivity (ε_0) – epsilon_0, eps_0, eps0, electric_constant

  • volt (V)

  • volt_ampere (VA)

  • von_klitzing_constant (R_K)

  • water_density_4C (ρH2O_4C)

  • water_density_60F (ρH2O_60F)

  • watt (W)

  • watt_hour (Wh) – watthour

  • weber (Wb)

  • week

  • wien_frequency_displacement_law_constant

  • wien_u

  • wien_wavelength_displacement_law_constant

  • wien_x

  • x_unit_Cu (Xu_Cu)

  • x_unit_Mo (Xu_Mo)

  • yard (yd) – international_yard

  • year (a) – yr, julian_year

  • zeta (ζ)

Unit systems#

A system is a named subset of units. Setting ureg.system = "imperial" (for example) changes which unit to_base_units() converts to. See Dealing with unit systems for more.

  • Planck (290 units)

  • SI (418 units)

  • US (72 units)

  • atomic (290 units)

  • cgs (302 units)

  • imperial (47 units)

  • mks (290 units)

Groups#

A group is a named subset of units, similar to a system.

  • Apothecary (4 units)

  • Avoirdupois (18 units)

  • AvoirdupoisUK (21 units)

  • AvoirdupoisUS (21 units)

  • ESU (12 units)

  • Gaussian (9 units)

  • ImperialVolume (12 units)

  • Printer (14 units)

  • Textile (8 units)

  • Troy (3 units)

  • USCSDryVolume (7 units)

  • USCSLengthInternational (14 units)

  • USCSLengthSurvey (14 units)

  • USCSLiquidVolume (8 units)

  • USCSVolumeOther (8 units)

  • international (290 units)

  • root (418 units)

Available contexts#

A context lets you convert between otherwise incompatible dimensions (e.g. wavelength and frequency) within a with ureg.context(...): block. See Contexts for more.

  • ESU – esu

  • Gaussian – Gau

  • boltzmann

  • chemistry – chem

  • energy

  • spectroscopy – sp

  • textile