100% JS's TOTP authenticator with no dependencies. You can use it in any javascript environment
npm install @14kay/totp-auth --save
import TOTPAuth from '@14kay/totp-auth'
const secret = 'JBSWY3DPEHPK3PXP'
const code = TOTPAuth.totp(secret) // 666666
const timeRemaining = OTPAuth.timeRemaining() // 15
const isLegal = OTPAuth.totpVerify('123456') // true or false