# Level

Level or levels may refer to:

## Engineering

• Level (instrument), a device used to measure true horizontal or relative heights
• Canal pound or level
• Regrading or levelling, the process of raising and/or lowering the levels of land
• Storey or level, of a building or a mine

## Science and mathematics

• Level (algebra), the lowest number of squares that sum to ${\displaystyle -1}$ in a field
• Level (logarithmic quantity), a logarithmic measure defined as the logarithm of a ratio of two like quantities, often expressed in decibels
• Energy levels, discrete amounts of energy that can be held by a quantum mechanical system or confined particle
• Classification levels, in biological organisation
• Level, the different values that a categorical variable can have
• Level, the different values that a factor can have in factor analysis
• Level, the different treatments that are applied within a factor in the design of experiments
• Spirit level, an instrument designed to indicate whether a surface is horizontal or vertical