SMS Authentication

Access to

Combine a unique identifier device (aka a mobile phone) with contextual data, and you have secure, user-friendly two-factor authentication with programmable, feature-rich APIs.

Authentication Header

Verify users and implement 2FA

without hassle

Secure your customers’ accounts and transactions with user-friendly two-factor authentication (2FA) with SMS and voice. Our feature-rich APIs help you verify new users, reduce fake accounts and spam, build user trust, and minimize account takeovers with channels that don’t require smartphones, apps or data connection.


The most popular way to send one-time passcodes is easy to integrate into your existing authentication infrastructure and services.


A feature-rich, robust API that detects the phone number type (mobile or landline) and sends the passcode via the appropriate channel (SMS or voice). Complete with multi-language and customization support.
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2FA Smart Contract

World’s first smart contract built to connect Blockchain applications to a 2FA API in the real world. Find out how tyntec connects the on-chain and off-chain applications.

Use Cases

Here are some great ways

to use Authentication in your business

Authentication Explained

Clear and Concise

Authentication made easy

This is how it works


Authentication How it Works
Authentication made easy - This is how it works

1. User registers on your website or app and provides a mobile phone number for verification

2. tyntec’s API can automatically choose the channel to send the verification code (SMS or voice call) — or the enterprise may give the user the option to choose

3. Both SMS and voice trigger the enterprise’s web back-end and calls the tyntec 2FA API with the provided phone number

4. tyntec sends the user a unique one-time password (OTP) via SMS or voice call

5. User enters the OTP on the website or app to verify his identity

6. The enterprise’s back-end sends an API call to the tyntec 2FA service and tyntec replies, confirming whether the OTP entered by the user is correct or not

7. If the OTP is correct, the website back-end can authorize the registration.

Key factors to consider for your authentication method


When does authentication become really critical?

Is there a single most important factor when choosing an authentication method? (hint: users first)

Is authentication bad for Customer experience?

What are the pros and cons of different methods?

Why is SMS still the most popular delivery method for 2FA?

Choose which service

works best for you

2FA Demo

Prefer to test first?

Go ahead and send a passcode!

2FA Demo
Here’s a chance to test 2FA yourself. Simply type in your phone number below. Click SEND and we’ll send you a one-time passcode – either by text or voice. You can even select the language of your choice.
# Send an otp with minimum mandatory values:

curl \
-H "accept: application/json" \
-H "apikey: <YOUR_API_KEY>"

# Check an OTP code:

curl \
-X POST "<OTP_ID>/check?otpCode=<OTP_CODE>"
-H "accept: application/json" \
-H "apikey: <YOUR_API_KEY>"


Make the most of

tyntec's advanced features

Assured, speedy delivery

Using our direct connections to telecom operators, we ensure fast, secure delivery to the endpoint – and share the monitoring data with our customers.

Frictionless integration

Stronger authentication with less coding – welcome to our simple, robust authentication APIs. Developers can configure features according to their needs, including password generation, language templates and more.

Real-time verification

Building on our industry-leading number information service, we can dynamically adjust user authentication requirements depending on the threat level, using real-time phone number information such as roaming information, user location, and phone status (on/off).


Ready to start?

Get our REST API - and rest easy



Need an overview?

Read our authentication guide

MFA Guide

Transparent Pricing

  • Mobile Chat
    Send a message
    0.012 €
    Receive a message
    0 €
  • Voice
    Voice Calling
    To landline numbers
    0.003 €
    To mobile numbers
    0.338 €
  • Messaging
    Local SMS
    Send a message
    0.062 €
    Receive a message
    0 €
    Short Code
    3900 €
    1300 €
    Send a message
    0.086 €
    Receive a message
    0 €
    Virtual Phone Number - Landline
    1.11 €
    1.11 €
    Send a message
    0.085 €
    Receive a message
    0.013 €
    Virtual Phone Number - Mobile
    0 €
    33 €
    Send a message
    0.072 €
    Receive a message
    0 €
  • Number Information
    Portability Check
    Per successful query
    0.0019 €
  • Authentication
    Per successful authentication
    0.09 €

Ready to start?

Get in touch.

Our team is happy to provide you with a demo of our solutions and answer your sales questions.
Fill out the form and we will be in touch as soon as possible.

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Authentication made easy

How does our 2FA API work?

Find out how to secure your customer journey without sacrificing user-friendliness with tyntec’s 2FA API.