---
title: "Check if a number is valid"
description: "Validate if a number is finite and not NaN or Infinity in TypeScript."
date: "2025-10-02"
tags: ["typescript","math","validation","frontend"]
canonical: "/snippets/typescript/number/is-valid"
---

import { Code } from '@astrojs/starlight/components'
import Source from './is-valid.ts?raw'

## Check if a number is valid

A valid number is a finite number: `NaN`, `Infinity`, `-Infinity` are not valid.

<Code code={Source} lang="ts" title="is-valid.ts" wrap />