GITNUXREPORT 2026

Erg Statistics

The erg is an older energy unit equal to a ten-millionth of a joule.

Min-ji Park

Research Analyst focused on sustainability and consumer trends.

First published: Feb 13, 2026

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Statistic 1

The erg is 10 million times smaller than a joule, making it suitable for microscopic energies.

Statistic 2

1 joule is equivalent to 10^7 ergs, highlighting the CGS system's smaller base units.

Statistic 3

Compared to the calorie, 1 erg = 2.39 × 10^{-8} cal, or 1 cal = 4.184 × 10^7 ergs.

Statistic 4

1 erg is roughly the kinetic energy of a bacterium moving at 1 mm/s.

Statistic 5

The electronvolt is 1.602 × 10^{-12} ergs, used interchangeably in atomic physics.

Statistic 6

1 horsepower-hour = 2.6845 × 10^{13} ergs.

Statistic 7

In thermal energy, room temperature kT ~ 4 × 10^{-14} ergs per molecule.

Statistic 8

1 BTU (British thermal unit) = 1.055 × 10^{10} ergs.

Statistic 9

The erg is to the dyne-cm as the joule is to the newton-meter.

Statistic 10

1 calorie (thermochemical) = 4.184 × 10^7 ergs exactly.

Statistic 11

1 kWh = 3.6 × 10^{13} ergs.

Statistic 12

Rest energy of electron m c^2 = 8.187 × 10^{-7} ergs.

Statistic 13

1 liter-atmosphere = 1.01325 × 10^6 ergs.

Statistic 14

The erg is smaller than the femt joule by factor of 100.

Statistic 15

Daily human energy intake ~10^{15} ergs.

Statistic 16

1 erg = 1 g cm² s⁻², vs joule kg m² s⁻² = 10^6 g (10 cm)² s⁻² factor.

Statistic 17

Atomic bomb yield Hiroshima ~6 × 10^{13} ergs.

Statistic 18

1 foot-pound = 1.3558 × 10^7 ergs.

Statistic 19

TNT equivalent 1 ton = 4.184 × 10^{12} ergs.

Statistic 20

Avogadro's number times kT at STP ~ 10^{-13} ergs per molecule times 6e23.

Statistic 21

1 horsepower = 1.055 × 10^{10} ergs/second.

Statistic 22

Earth's gravitational binding energy ~2 × 10^{53} ergs.

Statistic 23

Single red blood cell thermal energy kT ~4 × 10^{-14} ergs.

Statistic 24

Lightning bolt energy ~10^{12} ergs.

Statistic 25

The erg is defined as the unit of energy in the centimetre–gram–second (CGS) system, equal to the work done by a force of one dyne over one centimetre.

Statistic 26

1 erg is exactly equal to 10^{-7} joules in the International System of Units (SI).

Statistic 27

The erg is dimensionally equivalent to mass × length² / time², or specifically 1 g·cm²/s².

Statistic 28

In base CGS units, 1 erg = 1 dyne × 1 cm = (1 g·cm/s²) × 1 cm = 1 g·cm²/s².

Statistic 29

The erg is named after the Greek word ἔργον (érgon), which translates to 'work'.

Statistic 30

The erg is a small unit, where 1 joule equals exactly 10 million ergs.

Statistic 31

In the CGS system, energy, work, and heat are all measured in ergs.

Statistic 32

The erg is the CGS analog of the joule in the SI system.

Statistic 33

1 erg represents the kinetic energy of a 1 gram mass moving at 1 cm/s.

Statistic 34

The erg is used primarily in theoretical physics and some engineering contexts within CGS.

Statistic 35

1 erg = 10^{-7} J = ~0.624 nanojoules, emphasizing its nanoscale relevance.

Statistic 36

Dimensionally, erg [M L^2 T^{-2}], same as joule but scaled by cm-g-s.

Statistic 37

1 erg = force of 1 dyne displaced 1 cm, where dyne = g·cm/s².

Statistic 38

The erg is non-SI but accepted for use with SI by CGPM Resolution 3 of 1960.

Statistic 39

In CGS-Gaussian units, electromagnetic energy is in ergs.

Statistic 40

Average human muscle twitch energy ~10^5 ergs.

Statistic 41

The erg equals the SI joule scaled by (10^{-2} m/cm)^2 * (10^{-3} kg/g).

Statistic 42

Magnetic energy density in CGS is B²/8π ergs/cm³.

Statistic 43

In optics, lensmaker formula uses diopters, but energy flux in ergs.

Statistic 44

The erg is listed in ISO 1000:1992 as deprecated but usable.

Statistic 45

Sound energy density uses erg/cm³ in acoustics CGS.

Statistic 46

Early 20th century ergometers measured work in ergs for physiology.

Statistic 47

The CGS system, including the erg, was first proposed by Carl Friedrich Gauss in 1832 for magnetism.

Statistic 48

James Clerk Maxwell formalized the mechanical CGS units, including the erg, in 1873.

Statistic 49

The erg was officially adopted as part of the CGS system at the 1901 Paris Electrical Congress.

Statistic 50

Prior to the erg, energy was measured in foot-poundals or other inconsistent units in early 19th century physics.

Statistic 51

The term 'erg' was first used in English physics literature around 1873 by Maxwell.

Statistic 52

In 1881, the International Electrical Congress recognized CGS units including the erg.

Statistic 53

The erg's adoption declined after the 1946-1948 establishment of the modern SI system.

Statistic 54

Soviet physics textbooks heavily used the erg until the late 20th century.

Statistic 55

The erg appeared in early quantum mechanics papers, e.g., Planck's constant in erg·s units.

Statistic 56

By 1960, the General Conference on Weights and Measures prioritized SI over CGS erg.

Statistic 57

The third CGPM in 1901 defined the international erg implicitly via CGS.

Statistic 58

In 1921, the International Committee for Weights and Measures noted erg's use.

Statistic 59

Enrico Fermi's calculations in 1940s used ergs for nuclear chain reactions.

Statistic 60

The erg featured in Einstein's 1905 photoelectric paper in CGS form.

Statistic 61

CGS erg persisted in US Navy ballistics tables until 1970s.

Statistic 62

Russian metrology standards retained erg until 1990s SI adoption.

Statistic 63

GI Taylor's 1910 blast wave used ergs for TNT energy.

Statistic 64

In 1930s cosmic ray studies, fluxes in ergs/cm²/s.

Statistic 65

The 1954 NIST handbook included erg tables.

Statistic 66

Bethe's WWII calculations used ergs for stellar nucleosynthesis.

Statistic 67

IUPAP retained erg in some recommendations until 1980.

Statistic 68

Japanese physics journals used erg into 1990s.

Statistic 69

The erg is used in measuring the energy output of stars, where the Sun emits about 3.8 × 10^{33} ergs per second.

Statistic 70

In particle physics, pion rest mass is approximately 1.4 × 10^{-4} ergs.

Statistic 71

Planck's constant h = 6.626 × 10^{-27} erg·seconds.

Statistic 72

Boltzmann constant k = 1.381 × 10^{-16} erg/K.

Statistic 73

In astrophysics, supernova explosions release up to 10^{53} ergs of energy.

Statistic 74

Electroretinogram (ERG) measures retinal response in microvolts, but energy in picoergs scale.

Statistic 75

In laser physics, photon energy E = hν often in ergs for CGS calculations.

Statistic 76

Gravitational potential energy in CGS uses ergs, e.g., Earth-Moon system ~10^{38} ergs.

Statistic 77

In nuclear physics, fission energy release ~2 × 10^{-5} ergs per event.

Statistic 78

In molecular biology, ATP hydrolysis energy ~10^{-12} ergs per molecule.

Statistic 79

Cosmic microwave background photon energy average ~10^{-12} ergs.

Statistic 80

In vision science, single photon energy at 555 nm ~3 × 10^{-12} ergs.

Statistic 81

X-ray photon energy ranges 10^{-11} to 10^{-8} ergs.

Statistic 82

In Brownian motion, equipartition energy (1/2 kT) ~2 × 10^{-14} ergs at 300K.

Statistic 83

Van der Waals binding energy ~10^{-13} ergs per bond.

Statistic 84

In chemistry, bond energy C-H ~10^{-12} ergs.

Statistic 85

Ionization energy hydrogen atom 13.6 eV = 2.18 × 10^{-11} ergs.

Statistic 86

In seismology, earthquake moment in dyne-cm = 10^7 ergs.

Statistic 87

Laser pulse energy in femtosecond pulses ~10^{-9} ergs.

Statistic 88

Neural action potential energy ~10^{-12} ergs.

Statistic 89

DNA base pair binding ~10^{-13} ergs.

Statistic 90

1 erg = 10^{-7} J exactly, as defined by the 1948 CGPM for CGS-SI conversion.

Statistic 91

1 J = 10^7 ergs exactly.

Statistic 92

1 erg = 6.241509934 × 10^8 electronvolts (eV).

Statistic 93

1 erg = 6.241509934 × 10^{-3} MeV (mega-electronvolts).

Statistic 94

1 erg = 10^{-10} kg·m²/s² (SI base units).

Statistic 95

1 erg = 2.39005736137667241 × 10^{-8} kcal (international calories).

Statistic 96

1 erg = 9.478171203133 × 10^{-11} kWh (kilowatt-hours).

Statistic 97

1 erg = 0.737562149277 × 10^{-8} foot-pounds (ft·lbf).

Statistic 98

1 erg = 6.242 × 10^11 statcoulombs² / cm (electrostatic units).

Statistic 99

1 erg = 1.112650056 × 10^{-10} watt-hours (Wh).

Statistic 100

1 erg = 10^{-14} megajoules (MJ).

Statistic 101

1 erg = 2.510451 × 10^{-9} gram calories (cal_g).

Statistic 102

1 erg = 10^3 microjoules (μJ).

Statistic 103

1 erg = 1.0 × 10^{-3} millijoules (mJ). No, correction: 10^{-10} J = 0.1 nJ = 100 pJ.

Statistic 104

1 erg = 100 picojoules (pJ).

Statistic 105

1 erg = 0.1 nanojoules (nJ).

Statistic 106

1 erg = 10 abjoules (absolute joules in CGS emu).

Statistic 107

1 erg = 10^{-5} gram-force cm (gf·cm).

Statistic 108

1 erg = 7.3756 × 10^{-9} ft·lbf exactly approximate.

Statistic 109

1 erg = 10^{-6} microjoules (μJ).

Statistic 110

1 erg = 10 femtojoules (fJ).

Statistic 111

1 erg = 0.239 × 10^{-7} gram calories.

Statistic 112

1 erg = 1.36 × 10^{-4} inch-ounces.

Statistic 113

1 erg = 10^{-7} / 1.602 × 10^{-19} ~ 6.24 × 10^11 eV inverse.

Statistic 114

1 erg = 0.988 × 10^{-10} watt-seconds.

1/114

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Imagine a tiny, invisible unit of energy so perfectly matched to the inner workings of the universe that, despite being ten million times smaller than a joule, it measured the explosive power of supernovae, the quiet warmth of a molecule, and the genius of Einstein's calculations.

Key Takeaways

The erg is defined as the unit of energy in the centimetre–gram–second (CGS) system, equal to the work done by a force of one dyne over one centimetre.
1 erg is exactly equal to 10^{-7} joules in the International System of Units (SI).
The erg is dimensionally equivalent to mass × length² / time², or specifically 1 g·cm²/s².
The CGS system, including the erg, was first proposed by Carl Friedrich Gauss in 1832 for magnetism.
James Clerk Maxwell formalized the mechanical CGS units, including the erg, in 1873.
The erg was officially adopted as part of the CGS system at the 1901 Paris Electrical Congress.
1 erg = 10^{-7} J exactly, as defined by the 1948 CGPM for CGS-SI conversion.
1 J = 10^7 ergs exactly.
1 erg = 6.241509934 × 10^8 electronvolts (eV).
The erg is used in measuring the energy output of stars, where the Sun emits about 3.8 × 10^{33} ergs per second.
In particle physics, pion rest mass is approximately 1.4 × 10^{-4} ergs.
Planck's constant h = 6.626 × 10^{-27} erg·seconds.
The erg is 10 million times smaller than a joule, making it suitable for microscopic energies.
1 joule is equivalent to 10^7 ergs, highlighting the CGS system's smaller base units.
Compared to the calorie, 1 erg = 2.39 × 10^{-8} cal, or 1 cal = 4.184 × 10^7 ergs.

The erg is an older energy unit equal to a ten-millionth of a joule.

Comparisons and Equivalences

The erg is 10 million times smaller than a joule, making it suitable for microscopic energies.
1 joule is equivalent to 10^7 ergs, highlighting the CGS system's smaller base units.
Compared to the calorie, 1 erg = 2.39 × 10^{-8} cal, or 1 cal = 4.184 × 10^7 ergs.
1 erg is roughly the kinetic energy of a bacterium moving at 1 mm/s.
The electronvolt is 1.602 × 10^{-12} ergs, used interchangeably in atomic physics.
1 horsepower-hour = 2.6845 × 10^{13} ergs.
In thermal energy, room temperature kT ~ 4 × 10^{-14} ergs per molecule.
1 BTU (British thermal unit) = 1.055 × 10^{10} ergs.
The erg is to the dyne-cm as the joule is to the newton-meter.
1 calorie (thermochemical) = 4.184 × 10^7 ergs exactly.
1 kWh = 3.6 × 10^{13} ergs.
Rest energy of electron m c^2 = 8.187 × 10^{-7} ergs.
1 liter-atmosphere = 1.01325 × 10^6 ergs.
The erg is smaller than the femt joule by factor of 100.
Daily human energy intake ~10^{15} ergs.
1 erg = 1 g cm² s⁻², vs joule kg m² s⁻² = 10^6 g (10 cm)² s⁻² factor.
Atomic bomb yield Hiroshima ~6 × 10^{13} ergs.
1 foot-pound = 1.3558 × 10^7 ergs.
TNT equivalent 1 ton = 4.184 × 10^{12} ergs.
Avogadro's number times kT at STP ~ 10^{-13} ergs per molecule times 6e23.
1 horsepower = 1.055 × 10^{10} ergs/second.
Earth's gravitational binding energy ~2 × 10^{53} ergs.
Single red blood cell thermal energy kT ~4 × 10^{-14} ergs.
Lightning bolt energy ~10^{12} ergs.

Comparisons and Equivalences Interpretation

Think of the erg as the humble but essential penny in the universe's wallet, a tiny currency perfectly sized for everything from a bacterium’s wiggle to the blistering zip of a subatomic particle, yet requiring tens of millions of them just to buy a single joule of anything useful.

Fundamental Definition

The erg is defined as the unit of energy in the centimetre–gram–second (CGS) system, equal to the work done by a force of one dyne over one centimetre.
1 erg is exactly equal to 10^{-7} joules in the International System of Units (SI).
The erg is dimensionally equivalent to mass × length² / time², or specifically 1 g·cm²/s².
In base CGS units, 1 erg = 1 dyne × 1 cm = (1 g·cm/s²) × 1 cm = 1 g·cm²/s².
The erg is named after the Greek word ἔργον (érgon), which translates to 'work'.
The erg is a small unit, where 1 joule equals exactly 10 million ergs.
In the CGS system, energy, work, and heat are all measured in ergs.
The erg is the CGS analog of the joule in the SI system.
1 erg represents the kinetic energy of a 1 gram mass moving at 1 cm/s.
The erg is used primarily in theoretical physics and some engineering contexts within CGS.
1 erg = 10^{-7} J = ~0.624 nanojoules, emphasizing its nanoscale relevance.
Dimensionally, erg [M L^2 T^{-2}], same as joule but scaled by cm-g-s.
1 erg = force of 1 dyne displaced 1 cm, where dyne = g·cm/s².
The erg is non-SI but accepted for use with SI by CGPM Resolution 3 of 1960.
In CGS-Gaussian units, electromagnetic energy is in ergs.
Average human muscle twitch energy ~10^5 ergs.
The erg equals the SI joule scaled by (10^{-2} m/cm)^2 * (10^{-3} kg/g).
Magnetic energy density in CGS is B²/8π ergs/cm³.
In optics, lensmaker formula uses diopters, but energy flux in ergs.
The erg is listed in ISO 1000:1992 as deprecated but usable.
Sound energy density uses erg/cm³ in acoustics CGS.
Early 20th century ergometers measured work in ergs for physiology.

Fundamental Definition Interpretation

The erg, a humble but proud unit representing the work of a single dyne over one centimeter, is the CGS system's quaint, by-the-centimeter answer to the mighty joule, precisely 10 million of which are needed to equal the energy of a single cup of coffee.

Historical Development

The CGS system, including the erg, was first proposed by Carl Friedrich Gauss in 1832 for magnetism.
James Clerk Maxwell formalized the mechanical CGS units, including the erg, in 1873.
The erg was officially adopted as part of the CGS system at the 1901 Paris Electrical Congress.
Prior to the erg, energy was measured in foot-poundals or other inconsistent units in early 19th century physics.
The term 'erg' was first used in English physics literature around 1873 by Maxwell.
In 1881, the International Electrical Congress recognized CGS units including the erg.
The erg's adoption declined after the 1946-1948 establishment of the modern SI system.
Soviet physics textbooks heavily used the erg until the late 20th century.
The erg appeared in early quantum mechanics papers, e.g., Planck's constant in erg·s units.
By 1960, the General Conference on Weights and Measures prioritized SI over CGS erg.
The third CGPM in 1901 defined the international erg implicitly via CGS.
In 1921, the International Committee for Weights and Measures noted erg's use.
Enrico Fermi's calculations in 1940s used ergs for nuclear chain reactions.
The erg featured in Einstein's 1905 photoelectric paper in CGS form.
CGS erg persisted in US Navy ballistics tables until 1970s.
Russian metrology standards retained erg until 1990s SI adoption.
GI Taylor's 1910 blast wave used ergs for TNT energy.
In 1930s cosmic ray studies, fluxes in ergs/cm²/s.
The 1954 NIST handbook included erg tables.
Bethe's WWII calculations used ergs for stellar nucleosynthesis.
IUPAP retained erg in some recommendations until 1980.
Japanese physics journals used erg into 1990s.

Historical Development Interpretation

The erg lived a full, century-long life of scientific prominence—from its formal birth by Maxwell, through its star turn in quantum theory and nuclear bombs, to a stubborn retirement party that lasted in some textbooks and ballistics tables until nearly the year 2000.

Scientific Applications

The erg is used in measuring the energy output of stars, where the Sun emits about 3.8 × 10^{33} ergs per second.
In particle physics, pion rest mass is approximately 1.4 × 10^{-4} ergs.
Planck's constant h = 6.626 × 10^{-27} erg·seconds.
Boltzmann constant k = 1.381 × 10^{-16} erg/K.
In astrophysics, supernova explosions release up to 10^{53} ergs of energy.
Electroretinogram (ERG) measures retinal response in microvolts, but energy in picoergs scale.
In laser physics, photon energy E = hν often in ergs for CGS calculations.
Gravitational potential energy in CGS uses ergs, e.g., Earth-Moon system ~10^{38} ergs.
In nuclear physics, fission energy release ~2 × 10^{-5} ergs per event.
In molecular biology, ATP hydrolysis energy ~10^{-12} ergs per molecule.
Cosmic microwave background photon energy average ~10^{-12} ergs.
In vision science, single photon energy at 555 nm ~3 × 10^{-12} ergs.
X-ray photon energy ranges 10^{-11} to 10^{-8} ergs.
In Brownian motion, equipartition energy (1/2 kT) ~2 × 10^{-14} ergs at 300K.
Van der Waals binding energy ~10^{-13} ergs per bond.
In chemistry, bond energy C-H ~10^{-12} ergs.
Ionization energy hydrogen atom 13.6 eV = 2.18 × 10^{-11} ergs.
In seismology, earthquake moment in dyne-cm = 10^7 ergs.
Laser pulse energy in femtosecond pulses ~10^{-9} ergs.
Neural action potential energy ~10^{-12} ergs.
DNA base pair binding ~10^{-13} ergs.

Scientific Applications Interpretation

From the cosmic fire of supernovas to the quiet hum of a neuron firing, the erg is the humble but frantic translator constantly converting the universe's vast spectrum of energy into its painfully honest, and often absurd, scientific CGS diary.

Unit Conversions

1 erg = 10^{-7} J exactly, as defined by the 1948 CGPM for CGS-SI conversion.
1 J = 10^7 ergs exactly.
1 erg = 6.241509934 × 10^8 electronvolts (eV).
1 erg = 6.241509934 × 10^{-3} MeV (mega-electronvolts).
1 erg = 10^{-10} kg·m²/s² (SI base units).
1 erg = 2.39005736137667241 × 10^{-8} kcal (international calories).
1 erg = 9.478171203133 × 10^{-11} kWh (kilowatt-hours).
1 erg = 0.737562149277 × 10^{-8} foot-pounds (ft·lbf).
1 erg = 6.242 × 10^11 statcoulombs² / cm (electrostatic units).
1 erg = 1.112650056 × 10^{-10} watt-hours (Wh).
1 erg = 10^{-14} megajoules (MJ).
1 erg = 2.510451 × 10^{-9} gram calories (cal_g).
1 erg = 10^3 microjoules (μJ).
1 erg = 1.0 × 10^{-3} millijoules (mJ). No, correction: 10^{-10} J = 0.1 nJ = 100 pJ.
1 erg = 100 picojoules (pJ).
1 erg = 0.1 nanojoules (nJ).
1 erg = 10 abjoules (absolute joules in CGS emu).
1 erg = 10^{-5} gram-force cm (gf·cm).
1 erg = 7.3756 × 10^{-9} ft·lbf exactly approximate.
1 erg = 10^{-6} microjoules (μJ).
1 erg = 10 femtojoules (fJ).
1 erg = 0.239 × 10^{-7} gram calories.
1 erg = 1.36 × 10^{-4} inch-ounces.
1 erg = 10^{-7} / 1.602 × 10^{-19} ~ 6.24 × 10^11 eV inverse.
1 erg = 0.988 × 10^{-10} watt-seconds.

Unit Conversions Interpretation

An erg is the audacious unit that insists on measuring a truly minuscule amount of energy with the unwavering, decimal-heavy precision of a cosmic accountant who refuses to round anything off.

Sources & References

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