Planck Constant Over Two Pi
Part of Math Symbols
Planck Constant Over Two Pi has no standard Windows Alt code. Copy the character directly, or use its HTML entity or Unicode value instead.
- Alt code
- None
- HTML entity
- ℏ
- Unicode
- U+210F
About this symbol
ℏ, read as h-bar, is the reduced Planck constant: Planck’s constant divided by 2π. The symbol was introduced by the physicist Paul Dirac, and it appears throughout quantum physics, which is why it is sometimes called Dirac’s constant.
Unicode facts
- Official name
- PLANCK CONSTANT OVER TWO PI
- Also called
- Reduced Planck constant, Dirac constant
- Type
- Lowercase letter
- Unicode block
- Letterlike Symbols
- Added in
- Unicode 1.1 (1993)
- Related
- ћ Cyrillic Small Letter Tshe U+045B
Click the symbol or any value at the top of the page to copy it. See the full Math Symbols chart for related characters.