# expandedToStandardUncertainty

> Converts an expanded uncertainty (as reported by labs, usually k = 2) to the one-sigma valueprecision stored in .well files.

> **expandedToStandardUncertainty**(`expanded`, `coverageFactor?`): `number`

Converts an expanded uncertainty (as reported by labs, usually k = 2) to
the one-sigma `value_precision` stored in `.well` files.

## Parameters

### expanded

`number`

### coverageFactor?

`number` = `2`

## Returns

`number`