---
url: 'https://www.corbado.com/glossary/otp'
title: 'OTP (One-Time Password)'
description: 'Dive deep into the concept of OTP (One-Time Passcode) and understand how it''s revolutionizing the world of passwordless authentication methods.'
lang: 'en'
keywords: 'otp (one-time password)'
---

# OTP (One-Time Password)

## What is a One-Time Passcode (OTP)?

A **One-Time Passcode (OTP)** is a unique and temporary code generated for authentication
purposes, typically used in conjunction with or as an alternative to traditional
passwords. Leveraging OTPs:

- **Enhances security:** By being valid for only a short duration or single use, OTPs
  minimize the risks associated with compromised credentials.
- **Promotes passwordless authentication:** With OTPs, systems can bypass the need for
  fixed passwords, moving towards a passwordless future.
- **Improves user experience:** Users can authenticate without remembering complex
  passwords, often receiving OTPs via SMS, email, or dedicated authentication apps.

## Key Takeaways

> - A **One-Time Passcode (OTP)** is a unique, temporary code used for authentication.
> - OTPs play a crucial role in advancing
>   [passwordless authentication](https://www.corbado.com/glossary/passwordless-authentication).
> - They offer heightened security and a better user experience compared to traditional
>   passwords.

---

### Origins of OTPs in Digital Security

Before the rise of sophisticated hacking tools, static passwords sufficed. As cyber
threats evolved, the need for stronger authentication methods emerged. Enter OTPs. This
dynamic form of authentication added an extra layer of security, rendering stolen
credentials useless after a single use.

### Technical Implications of OTPs

- **Delivery Methods:** OTPs can be delivered in various ways including SMS, emails, or
  through applications like Google [Authenticator](https://www.corbado.com/glossary/authenticator) or Authy.
- **Time-based vs Counter-based:** Time-based OTPs (TOTP) are valid for a specific
  duration, while counter-based OTPs change after a certain number of uses.
- **Integration with Systems:** Integrating OTPs into systems usually requires
  communication with an SMS gateway or authentication API.

### The Role of OTPs in Passwordless Authentication

The digital world is moving towards passwordless methods, and OTPs are a significant step
in that direction. Instead of relying on a password that users might forget, OTPs offer a
dynamic, secure, and user-friendly alternative.

---

## One-Time Passcode (OTP) FAQs

### What is the advantage of E-Mail OTP?

The advantage of OTP via e-mail is the reduced costs, especially in contrast to SMS OTP.
Regarding security, of course it's important that the e-mail account of the user is not
compromised, but only accessible with secure authentication options.

### How does an OTP enhance security in passwordless authentication?

An OTP is temporary and unique, meaning that even if intercepted, it's of little use to
cybercriminals due to its short lifespan or single-use nature.

### Is receiving an OTP via SMS safe?

While SMS is a common delivery method for OTPs, it's not the most secure due to potential
[SIM swapping](https://www.corbado.com/faq/sim-swapping-sms-authentication-risk) or interception risks. Using
dedicated authentication apps or hardware tokens can offer greater security.

### How do OTPs fit into the broader context of multi-factor authentication (MFA)?

OTPs are often a component of MFA. While a password (something you know) is one factor, an
OTP (something you receive) acts as a second, separate factor, enhancing security.