A Go module to validate CPF and CNPJ numbers (Brazilian people and companies unique identifier for the Federal Revenue).
The pseudo-acronym CNPF is a sort of tong-twister and a common typo when developers discuss the implementation of objects that could hold either a CPF or a CNPJ numbers.
package main
import "github.com/cuducos/go-cnpf"
func main() {
// these return true
cnpf.IsValid("23858488135")
cnpf.IsValid("238.584.881-35")
cnpf.IsValid("11222333000181")
cnpf.IsValid("11.222.333/0001-81")
cnpj.IsValid("12.ABC.345/01DE-35")
cnpj.IsValid("12ABC34501DE35")
// these return false
cnpf.IsValid("111.111.111-11")
cnpf.IsValid("11.111.111/1111-11")
cnpf.IsValid("123.456.769/01")
cnpf.IsValid("12.345.678 9012-34")
cnpf.IsValid("ABC.DEF.GHI-JK")
cnpf.IsValid("AB.CDE.FGH/IJKL-MN")
cnpf.IsValid("123")
// these return 11111111111, 11111111111111 and 12ABC34501DE35
cnpf.Unmask("111.111.111-11")
cnpf.Unmask("11.111.111/1111-11")
cnpj.Unmask("12.ABC.345/01DE-35")
// this return 111.111.111-11, 11.111.111/1111-11 and 12.ABC.345/01DE-35
cnpf.Mask("11111111111")
cnpf.Mask("11111111111111")
cnpj.Mask("12ABC34501DE35")
}Important
Starting in July 2026 the CNPJ number will be alphanumeric. This package already supports the new format. If you do not want to support the new format, tag this package to v0.0.1.