Simple Checkout Fields Manager for WooCommerce - Validate CPF/CNPJ WP Registry grade A. No security issues foundWP RegistryNo security issues foundOpen the reportA

A companion plugin for Simple Checkout Fields Manager for WooCommerce that adds Brazilian tax ID fields to the WooCommerce Blocks checkout and validates them server-side.

What it does

This plugin provides two things:

1. Bundled field definitions

The file swcbcf-fields-cpf-cnpj.json contains four ready-to-import contact fields:

Import this file once via the main plugin's Tools → Import field definitions tool. The fields will then appear on your WooCommerce Blocks checkout for Brazilian customers.

This plugin also adds live input masking to the CPF (999.999.999-99) and CNPJ (XX.XXX.XXX/XXXX-99) fields on the Blocks checkout, so customers see the formatting characters as they type. Either formatted or unformatted input is accepted (see examples below); the order is always stored with the punctuation stripped, regardless of what was typed or pasted.

2. Server-side CPF and CNPJ validation

Once active, the plugin validates CPF and CNPJ values submitted at checkout:

• Checks that the value has the correct number of characters (11 for CPF, 14 for CNPJ)
• Rejects values made up of a single repeated character (e.g. 00000000000)
• Verifies both check digits using the official Brazilian algorithm

Validation errors are returned to the customer inline, preventing the order from being placed with an invalid tax ID.

CPF examples

Examples of valid CPFs accepted by this plugin:

CNPJ format: old (numeric) and new (alphanumeric)

Starting July 2026, Receita Federal allows the CNPJ base (the first 12 characters) to contain uppercase letters as well as digits; the last 2 check digits remain numeric. This is defined in Ato Declaratório Executivo COCAD nº 141102.

This plugin validates both formats — the previous all-numeric CNPJ and the new alphanumeric one — using the same official check-digit algorithm (each character's value is its ASCII code minus 48, so digits 0-9 give values 0-9 and letters A-Z give values 17-42).

Examples of valid CNPJs accepted by this plugin:

Requirements

• WordPress 6.3 or higher
• WooCommerce 8.9 or higher (with the Blocks checkout active)
• PHP 7.4 or higher
• Simple Checkout Fields Manager for WooCommerce 7.3 or higher – the main plugin this one extends

Installation

1. Install and activate Simple Checkout Fields Manager for WooCommerce.
2. In your WordPress admin, go to the main plugin's settings and use Tools → Import field definitions to import swcbcf-fields-cpf-cnpj.json (found in this plugin's directory).
3. Install and activate this plugin. Validation is enabled automatically — no further configuration needed.

Further reading

See the accompanying blog post (in Brazilian Portuguese and English) for a step-by-step walkthrough:

Como adicionar os campos de Pessoa Jurídica, CPF, CNPJ, e Inscrição Estadual no checkout de blocos do WooCommerce

Author

Naked Cat Plugins by Webdados