Verify users,
pay for verifications

nOTP is an innovative product that allows you to authenticate and verify users without any actions from their end. Available as an SDK currently for Android phones, it works much faster than the typical OTP verification. The beauty – It works without an SMS. Hence the name nOTP. Getit?


Time to think beyond OTPs

Two-Factor authentication

nOTP can help you add a layer of security to apps without adding complexity for your users


Resetting password

Instead of sending codes via email or SMS, nOTP is a hassle-free way to verify users before password resets.


Passwordless logins & authentication

Users do not have to remember passwords and can simply be verified using nOTP every time they log in.


Prevention of spam

Instant verification allows you to stop spam registrations and avoid fake users from signing on.


How it works


Customer clicks the “verify” button on the app


Exotel verification

Exotel makes an automated outbound call to the number specified in the app.


Intercept call

Exotel SDK automatically intercepts the call, disconnects it and verifies the customer.


Number verified

Exotel then pings the server that the number is verified.


nOTP advantage for your business

Lower Cost

nOTP costs upto 40% less than traditional verification methods. Pay only for successful verifications

Seamless experience

This method of verification requires no action from the user’s end, making it a seamless experience

Higher success rate

nOTP has a higher success rate compared to SMS verifications since there is no scope for delivery failures

nOTP savings calculator


Monthly Cost for OTP


Monthly nOTP Cost


Annual savings on verifications

Exhaustive guide on 2 factor authentication

From SMS OTP, to OTP over call, to email OTP, to no OTP at all! We show how 2FA evolved over time.

What our customers have to say about Exotel

Shashank ND

We have worked across cloud telephony players and with other vendors, but the fact is Exotel is dependable.

Co-Founder & CEO, Practo

Praveen Kumar

Exotel's APIs are very clearly defined. Our tech team could integrate them in no time. It’s easy to incorporate into any product.

Assistant Vice President, Quikr Services

Kumar Vinod

We used to use a traditional PBX system before. But that doesn’t have the capabilities of Exotel’s IVR system. So, we decided to use Exotel for our IVR cancellation system.

Senior Manager - Operations, redBus


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Get Early Access for nOTP

We’ll help you setup nOTP SDK in your app

The Exotel Advantage

Superior Quality

Best success rates, voice quality and reduced latency

Scale at Ease

Grow at will, expand without worrying about infrastructure

Superior Reliability

Best in class uptimes of 99.94% including operator uptimes

Best Support

18×7 customer support via phone, email and Twitter

Simple to implement

Sign up and get started in less than 30 minutes, integrate easily using our REST APIs

Extensive Reporting

Easy to understand, detailed reports sent every day

Find out how Exotel can work for you. Set up a call.

We take away some of the biggest pain points of traditional systems like EPABX.



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