# E Constant

Use E in Calcul.io. See what this built-in constant represents, enter it in an editable calculation, and review related values and units.

## e

Try it yourself:

```calculio
e
e ^ 2
exp(2)
log(e)
```

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## Euler’s Number e

**e** is the base of natural logarithms, approximately 2.71828. It describes continuous growth and exponential decay.

## Exponents and logs

Use [exp()](https://calcul.io/function/exp/index.md) for e raised to a value and [log()](https://calcul.io/function/log/index.md) for its inverse. Exponential arguments should be dimensionless; scale physical values before use.

[All constants](https://calcul.io/constants/index.md)