otplib API Documentation / @otplib/totp / generateSync

Function: generateSync()

generateSync(options): string

Defined in: totp/src/index.ts:173

Generate a Time-based One-Time Password (TOTP) synchronously

This is the synchronous version of generate. It requires a crypto plugin that supports synchronous HMAC operations (e.g., NodeCryptoPlugin or NobleCryptoPlugin). Using this with WebCryptoPlugin will throw an error.

Parameters

options

TOTPGenerateOptions

TOTP generation options

Returns

string

The TOTP code as a string

See

• generate for the async version
• RFC 6238 Section 4

Throws

If the algorithm is invalid or unsupported by the plugin

Throws

If HMAC computation fails or the plugin does not support sync operations

Example

import { generateSync } from '@otplib/totp';
import { NodeCryptoPlugin } from '@otplib/plugin-crypto-node';

const totp = generateSync({
  secret: new Uint8Array([1, 2, 3, 4, 5]),
  epoch: Math.floor(Date.now() / 1000),
  period: 30,
  digits: 6,
  crypto: new NodeCryptoPlugin(),
});
// Returns: '123456'