Energy Converter
Convert between joules, calories, BTU, kilowatt hours, and other energy units with professional precision and instant results.
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Energy Converter
Convert between joules, calories, BTU, and other energy units with precision.
Understanding Energy Measurement Systems
SI Units (International System)
The standard scientific energy measurement system
- • Joule (J) - Base unit of energy
- • Kilojoule (kJ) - 1,000 joules
- • Megajoule (MJ) - 1,000,000 joules
- • Gigajoule (GJ) - 1,000,000,000 joules
Electrical Units
Energy consumption and generation
- • Watt Hour (Wh) - Basic electrical energy
- • Kilowatt Hour (kWh) - Household electricity
- • Megawatt Hour (MWh) - Industrial scale
- • Gigawatt Hour (GWh) - Power plant scale
Thermal Units
Heat energy and thermal systems
- • Calorie (cal) - Heat to warm 1g water 1°C
- • Kilocalorie (kcal) - Food energy
- • BTU - British Thermal Unit
- • Therm - Natural gas energy
Atomic & Nuclear Units
Particle physics and nuclear energy
- • Electron Volt (eV) - Atomic scale energy
- • Kiloelectron Volt (keV) - X-ray energy
- • Megaelectron Volt (MeV) - Nuclear reactions
- • Gigaelectron Volt (GeV) - Particle accelerators
Essential Conversion Factors
Common Conversions
Quick Approximations
Scientific Units
Professional Applications
Electrical Engineering
- • Power system design and analysis
- • Energy storage system sizing
- • Electrical load calculations
- • Motor and generator specifications
- • Power quality assessments
HVAC Systems
- • Heating and cooling load calculations
- • Energy efficiency ratings
- • Thermal comfort analysis
- • Building energy modeling
- • Heat pump performance evaluation
Renewable Energy
- • Solar panel energy output
- • Wind turbine performance
- • Battery storage capacity
- • Grid integration studies
- • Energy payback calculations
Nutrition & Food Science
- • Caloric content analysis
- • Metabolic rate calculations
- • Food labeling compliance
- • Dietary planning and assessment
- • Sports nutrition optimization
Physics & Research
- • Particle physics experiments
- • Nuclear reaction calculations
- • Spectroscopy analysis
- • Materials science research
- • Quantum mechanics studies
Automotive Industry
- • Fuel efficiency calculations
- • Electric vehicle range
- • Engine performance analysis
- • Emissions testing
- • Hybrid system optimization
Common Energy Examples
Everyday Energy
Transportation
Household & Industrial
What's the difference between calories and Calories?
A calorie (cal) is the energy to heat 1g of water by 1°C. A Calorie (Cal) or kilocalorie (kcal) equals 1,000 calories and is used in nutrition.
How do I convert between electrical and thermal energy?
Use the conversion: 1 kWh = 3.6 MJ = 860 kcal = 3,412 BTU. These conversions assume 100% efficiency.
What energy unit should I use for scientific calculations?
Use joules (J) for most scientific work. For atomic physics, use electron volts (eV). For large-scale energy, use megajoules (MJ) or gigajoules (GJ).
How accurate are these energy conversions?
Our conversions use internationally recognized constants and are accurate to 8+ decimal places, suitable for professional and scientific applications.