CPF and CNPJ in JavaScript and TypeScript

Validate, format and generate Brazilian tax IDs with the cpf library. Alphanumeric CNPJ support, built-in types and zero runtime dependencies.

01 / Input

Validate and format

Brazilian tax ID

Document type Document number

Validation uses the normalized original input. The mask is a formatting preview.

Processed locally. No document number is sent.

02 / Output

Result

Formatted preview: —

Output of format

Normalized value: —

Enter a document number or load an example.

Validation checks the structure and check digits. It does not verify issuance, ownership or registration status.

In your project

Installation and usage

Available for Node.js and browsers, with ESM and CommonJS exports.

npm install cpf

View the API reference

example.tsJavaScript / TypeScript

import cpf, { cnpj } from 'cpf'

cpf.isValid('529.982.247-25')
// true

cnpj.isValid('12.ABC.345/01DE-35')
// true

cpf.format('5299822')
// '529.982.2'

Documentation

Implementation guides

Read the documentation

Validate CPF

Validate CPF with or without formatting, preserve leading zeros and diagnose errors with the cpf library for JavaScript and TypeScript.

Alphanumeric CNPJ

Validate numeric and alphanumeric CNPJ, normalize lowercase letters and calculate check digits in JavaScript and TypeScript.

Masks and forms

Format complete or partial CPF and CNPJ values while preserving the cursor and validating the original input.

React integration

Build a React form with CPF and CNPJ validation, controlled inputs, accessible messages and formatting on blur.