# isNumeric() Function & Examples

Use the isNumeric() utils function in Calcul.io. Review its syntax, edit working examples, understand the result, and explore related math functions.

## isNumeric

#### isNumeric(x)

Try it yourself:

```calculio
isNumeric(2)
isNumeric("2")
hasNumericValue("2")
isNumeric(0)
isNumeric(bignumber(500))
isNumeric(fraction(0.125))
isNumeric(2 + 3i)
isNumeric([2.3, "foo", false])
```

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## isNumeric(): test numeric input

**isNumeric(x)** reports whether x is a numeric value. It is a first validation step when a calculation may receive text, empty data, or another type.

## Use precise validation

Numeric is broader than the domain required by many formulas. Follow it with [isFinite()](https://calcul.io/function/isFinite/index.md) to reject infinity, [isInteger()](https://calcul.io/function/isInteger/index.md) for counts, or [isPositive()](https://calcul.io/function/isPositive/index.md) for positive-only inputs.

## Practical workflow

Validate before calling [sqrt()](https://calcul.io/function/sqrt/index.md), [log()](https://calcul.io/function/log/index.md), or [division](https://calcul.io/function/divide/index.md). Each has additional domain rules, so a true isNumeric result alone is not sufficient.

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