OTP Code

Use strong authentication with an OTP (One Time Password) code

What is an OTP code?

An OTP code is a one-time password consisting of a random string of alphanumeric characters, generated by an authentication system. An SMS with an OTP code allows you to validate the mobile phone numbers of your users. This way, you have a guarantee that the number added by the user is valid and owned by them. The goal is to allow users to access a service securely: payment validation, registration validation, electronic signature…

Since 2014, SMS Partner has been sending OTP codes across Europe and Africa. Since SMS is used worldwide, you can use OTP code sending for your campaigns in France as well as internationally. Sending one-time passwords will help secure your solution.

Send your OTP codes in just a few clicks!

Send OTP codes

The benefits of strong SMS authentication

Helps combat cybercrime and reduce the risk of fraud on your system

Allows you to retrieve validated mobile numbers from your users via our SMS API.

OTP code authentication, how does it work?

Sending an SMS containing a code

Integrate your phone number database directly into the SMS Partner platform.

User enters the OTP code

Upon receiving the code, the user enters it on the platform.

Code validation

After entering the one-time code, it is validated through the client interface.

The price of an SMS with OTP code

TARIF OTP

SMS OTP

0.049€

HT/Code OTP

Other SMS services offered by the platform

Access all our SMS pages right now

Premium SMS Alert SMS Transactional SMS Voice SMS

Our guarantees for OTP sends

An OTP code is delivered in under 20 seconds (90% of the time)

Security guaranteed by our datacenter in Paris

24/7 monitoring carried out by our team of technicians

A secure and easy-to-integrate HTTPS API

FAQ sur les codes OTP

Where is the OTP code received?

In general, the OTP code is automatically sent by SMS, but it can also be delivered by email, depending on your preferences. It is received within seconds of the request. If you do not receive it, you can request a new one-time code.

What is the purpose of an OTP code?

SMS messages with OTP codes ensure the security of authentication processes. They are dynamic passwords, meaning hackers cannot predict or memorize them. Since one-time codes are only valid for a limited period of time, this leaves hackers too little time to steal credentials.

What are the different types of OTP codes?

There are two main types of OTP codes:

TOTP (Time-based OTP): The code is valid for a limited period of time. It is generated based on the current time and a secret key.
HOTP (HMAC-based OTP): The code is generated after a specific event (such as a login attempt) and remains valid until it is used.

Both methods strengthen security by making codes impossible to reuse.

What algorithms are used to generate OTP codes?

OTP codes are generated using cryptographic algorithms such as HMAC-SHA1, HMAC-SHA256, or HMAC-SHA512. These algorithms combine a secret key and a variable factor (time or event) to produce a unique, secure code.

Why did I receive an OTP code without requesting one?

An unsolicited OTP code may come from a technical bug on the website, a suspicious login attempt, or a third party entering your details by mistake. In any case, do not click on any associated links and do not share the code. Check your accounts for any suspicious activity. If you think you are the victim of a hacking attempt, change your passwords. Above all, do not hesitate to report it to the relevant customer support team.

How can I secure privileged access with OTP codes?

Privileged users (such as administrators) should benefit from enhanced two-factor authentication, including an OTP code. This limits the risk of unauthorized access to critical systems. It is also possible to configure contextual access rules (e.g., OTP required only from unusual locations).

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