Convert energy units — joules, kilowatt-hours, calories, BTU, electron volts and more.
| Unit | Name | Value |
|---|---|---|
| 0.001 cal | 41840 erg | |
| 0.01 cal | 418400 erg | |
| 0.1 cal | 4.184e+06 erg | |
| 1 cal | 4.184e+07 erg | |
| 5 cal | 2.092e+08 erg | |
| 10 cal | 4.184e+08 erg | |
| 50 cal | 2.092e+09 erg | |
| 100 cal | 4.184e+09 erg | |
| 1000 cal | 4.184e+10 erg |
Formula: Erg = Calorie × 4.184e+07
Multiply any calorie value by 4.184e+07 to get erg.
Reverse: Calorie = Erg × 2.3901e-8
Common calorie values — factor: 1 cal = 4.184e+07 erg
| Calorie (cal) | Erg (erg) | Context |
|---|---|---|
| 1 cal | 4.184e+07 erg | 1 cal |
| 5 cal | 2.092e+08 erg | 5 cal |
| 10 cal | 4.184e+08 erg | Small candy |
| 50 cal | 2.092e+09 erg | 50 cal |
| 100 cal | 4.184e+09 erg | Short walk |
| 500 cal | 2.092e+10 erg | Snack |
| 1,000 cal | 4.184e+10 erg | Light meal |
| 5,000 cal | 2.092e+11 erg | Meal |
| 1e+04 cal | 4.184e+11 erg | Large meal |
| 5e+04 cal | 2.092e+12 erg | Daily intake fraction |
| 1e+05 cal | 4.184e+12 erg | 100 kcal |
| 5e+05 cal | 2.092e+13 erg | 500 kcal workout |
| 1e+06 cal | 4.184e+13 erg | 1 Mcal |
| 1.000e+09 cal | 4.184e+16 erg | 1 Gcal |
| 1.000e+12 cal | 4.184e+19 erg | 1 Tcal |
1 cal = 4.184e+07 erg. Memorize for instant estimates.
Use 4.184e+07 as a quick mental multiplier.
Multiply result by 2.3901e-8 to recover the original cal value.
Converts energy units for calculations and equipment specifications.
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The calorie (cal) was defined in 1824 as the heat needed to raise 1 gram of water by 1°C. There are two versions: the small calorie (cal = 4.184 J) and the large calorie or kilocalorie (kcal = 4,184 J), which is the 'Calorie' used in nutrition.
The calorie remains standard in chemistry for heat of reaction measurements. In the US, food packaging uses 'Calories' (with capital C) which are actually kilocalories — a persistent source of confusion.
Interesting fact: The confusion between cal and kcal means that a food label saying '200 Calories' actually means 200 kcal = 200,000 cal = 836,800 joules. The SI unit for food energy is the kilojoule.
The erg is the unit of energy in the CGS (centimeter-gram-second) system, equal to exactly 10⁻⁷ joules. It was defined by the British Association for the Advancement of Science in 1882 as the work done by a force of one dyne over one centimeter.
Ergs were widely used in 19th and early 20th century physics before SI standardization. They remain in use in astrophysics (stellar luminosities in erg/s) and some older scientific literature.
Interesting fact: The Sun radiates about 3.8 × 10³³ ergs per second. A mosquito in flight exerts about 100 ergs of energy per wingbeat. One joule = 10,000,000 ergs exactly.
Converting calorie to erg is common across energy, nutrition, engineering, and science. Different sectors use different energy units — joules in physics, kcal in nutrition, kWh in electricity, and BTU in HVAC — making accurate conversion essential for cross-disciplinary work and international comparisons.
Quick reference: 5 cal = 2.092e+08 erg and 10 cal = 4.184e+08 erg. Reverse: 1 erg = 2.3901e-8 cal. Exact factor: 1 cal = 4.184e+07 erg.
All conversions use IEEE 754 double-precision arithmetic, accurate to at least 8 significant figures.