Convert energy units — joules, kilowatt-hours, calories, BTU, electron volts and more.
| Unit | Name | Value |
|---|---|---|
| 0.001 kcal | 4.184e+07 erg | |
| 0.01 kcal | 4.184e+08 erg | |
| 0.1 kcal | 4.184e+09 erg | |
| 1 kcal | 4.184e+10 erg | |
| 5 kcal | 2.092e+11 erg | |
| 10 kcal | 4.184e+11 erg | |
| 50 kcal | 2.092e+12 erg | |
| 100 kcal | 4.184e+12 erg | |
| 1000 kcal | 4.184e+13 erg |
Formula: Erg = Kilocalorie × 4.184e+10
Multiply any kilocalorie value by 4.184e+10 to get erg.
Reverse: Kilocalorie = Erg × 2.3901e-11
Common kilocalorie values — factor: 1 kcal = 4.184e+10 erg
| Kilocalorie (kcal) | Erg (erg) | Context |
|---|---|---|
| 1 kcal | 4.184e+10 erg | 1 kcal snack |
| 10 kcal | 4.184e+11 erg | Small fruit |
| 50 kcal | 2.092e+12 erg | Cookie |
| 100 kcal | 4.184e+12 erg | Small snack |
| 200 kcal | 8.368e+12 erg | Light meal |
| 500 kcal | 2.092e+13 erg | Workout burn |
| 1,000 kcal | 4.184e+13 erg | Large meal |
| 2,000 kcal | 8.368e+13 erg | Daily intake |
| 2,500 kcal | 1.046e+14 erg | Active adult day |
| 5,000 kcal | 2.092e+14 erg | Marathon burn |
| 1e+04 kcal | 4.184e+14 erg | Ultra marathon |
| 5e+04 kcal | 2.092e+15 erg | Week intake |
| 1e+05 kcal | 4.184e+15 erg | Month intake |
| 1e+06 kcal | 4.184e+16 erg | Year intake |
| 1.000e+09 kcal | 4.184e+19 erg | Decade |
1 kcal = 4.184e+10 erg. Memorize for instant estimates.
Use 4.184e+10 as a quick mental multiplier.
Multiply result by 2.3901e-11 to recover the original kcal value.
Prescribes daily energy intake and food portion sizes in kcal.
Calculates calorie burn during workouts and links to dietary targets.
Measures energy content of food products for nutritional labeling.
Creates weight management plans based on daily kcal targets.
Optimizes pre/during/post workout nutrition using kcal calculations.
Calculates nutritional information per serving in kcal for labels.
The kilocalorie (kcal) equals 1,000 calories or 4,184 joules, and is the unit used on food labels worldwide (often written as 'Cal' with a capital C in the US). It was standardized by the International Table calorie in 1956.
Nutritionists, dietitians, and food scientists use kcal for daily energy intake recommendations. Most adults need 2,000–2,500 kcal/day. Exercise apps, fitness trackers, and dietary plans all operate on kcal.
Interesting fact: One gram of fat yields about 9 kcal, one gram of carbohydrate or protein yields about 4 kcal. A single sugar cube (4g) contains about 16 kcal.
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 kilocalorie 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 kcal = 2.092e+11 erg and 10 kcal = 4.184e+11 erg. Reverse: 1 erg = 2.3901e-11 kcal. Exact factor: 1 kcal = 4.184e+10 erg.
All conversions use IEEE 754 double-precision arithmetic, accurate to at least 8 significant figures.