Joule per square meter (J/m²)
SI unit of heat (energy) per area, for example solar radiation received per square meter.
What is a joule per square meter?
- Symbol
- J/m²
- Quantity
- Heat Density
- Unit system
- SI
- Definition
- SI unit of heat (energy) per area, for example solar radiation received per square meter.
- Exact
- Yes, the value is exact by definition
- Source
- SI Brochure, 9th edition (BIPM, 2019)
Common applications
The SI unit of energy per area, used in meteorology, radiation physics and laser work (fluence).
Joule per square meter in other heat density units
- 1 J/m² = 0.001 kJ/m²Kilojoule per square meter
- 1 J/m² = 0.000001 MJ/m²Megajoule per square meter
- 1 J/m² ≈ 2.777777778e-7 kWh/m²Kilowatt-hour per square meter
- 1 J/m² ≈ 0.00008805509184 BTU/ft²BTU per square foot
- 1 J/m² ≈ 0.00002390057361 LyLangley
Joule per square meter quick reference
| Joule per square meter | Kilojoule per square meter | BTU per square foot | Megajoule per square meter |
|---|---|---|---|
| 1 J/m² | = 0.001 kJ/m² | ≈ 0.00008805509184 BTU/ft² | = 0.000001 MJ/m² |
| 10 J/m² | = 0.01 kJ/m² | ≈ 0.0008805509184 BTU/ft² | = 0.00001 MJ/m² |
| 100 J/m² | = 0.1 kJ/m² | ≈ 0.008805509184 BTU/ft² | = 0.0001 MJ/m² |
| 1000 J/m² | = 1 kJ/m² | ≈ 0.08805509184 BTU/ft² | = 0.001 MJ/m² |
Where the joule per square meter fits
The next larger heat density unit is the kilojoule per square meter (kJ/m²). 1 J/m² = 0.001 kJ/m², and 1 kJ/m² = 1000 J/m².
Frequently asked questions
- How many kilojoules per square meter are in one joule per square meter?
- One joule per square meter = 0.001 kJ/m² (kilojoules per square meter).
- How many BTUs per square foot are in one joule per square meter?
- One joule per square meter ≈ 0.00008805509184 BTU/ft² (BTUs per square foot).
- How many megajoules per square meter are in one joule per square meter?
- One joule per square meter = 0.000001 MJ/m² (megajoules per square meter).