Voice OTP Services - The Ultimate Backup

Why Voice OTP?

Voice OTP involves making a computer-generated call to the user's phone number and dictating the One-Time Password. It serves as a crucial layer in a robust verification strategy.

While SMS is the standard, it isn't infallible. Network congestion, DND (Do Not Disturb) filters, or roaming issues can block texts. Voice OTP bypasses these text-based filters. Additionally, it provides accessibility for visually impaired users and allows verification on landline numbers, expanding your reach to demographics that SMS cannot serve effectively.

Key Benefits

Why you should add Voice OTP to your flow

Superior Fallback

When SMS delivery fails or times out, Voice OTP acts as an immediate and reliable backup, significantly increasing your overall verification success rate.

Accessibility

Voice calls are the most accessible verification method for users with visual impairments or low literacy, ensuring your app is inclusive for everyone.

Landline Support

Unlike SMS and WhatsApp, Voice OTP works on fixed landlines, making it essential for B2B applications or regions with high landline usage.

Global Coverage

Our voice network spans 200+ countries with high-quality routes, ensuring clear audio and reliable connection regardless of the user's location.

Spam Bypass

Voice calls are treated differently by carrier networks than SMS. They often bypass rigorous spam filters that might block transactional text messages.

Customization

Support for multiple languages and accents. Customize the speech text, speed, and repetition to provide the best user experience.

The Voice Verification Flow

1

Initiation

User requests OTP. If they choose "Call Me" or if SMS fails, a voice request is triggered.

2

Call Connection

Our system instantly places a call to the provided phone number using premium voice routes.

3

Text-to-Speech

Upon answering, a high-quality TTS engine reads out the OTP clearly (e.g., "Your code is 1... 2... 3...").

4

Verification

The user listens to the code (often repeated twice) and enters it into your application.

Simple Voice API

Adding voice capability is as easy as sending an SMS. Use the same API structure with a different endpoint.

View Full Documentation

voice_otp.php

$curl = curl_init();

$params = http_build_query(array(
    'apikey' => 'YOUR_API_KEY',
    'number' => '919876543210',
    'OTP' => '123456'
));

curl_setopt_array($curl, array(
  CURLOPT_URL => 'https://api.hanuotp.in/voice-otp.php?' . $params,
  CURLOPT_RETURNTRANSFER => true,
  CURLOPT_HTTPGET => true,
));

$response = curl_exec($curl);
curl_close($curl);

echo $response;

Frequently Asked Questions

Common questions about Voice OTP

Yes, our Text-to-Speech engine supports over 20 languages including English, Hindi, Spanish, French, and more. You can specify the language parameter in the API request.

You can configure the system to retry the call after a certain interval (e.g., 30 seconds) or trigger a different fallback method. You only pay for answered calls.

Voice calls generally cost slightly more than SMS due to telecom charges. However, given their high success rate as a fallback, the ROI is excellent for ensuring user conversion.

Currently, we support dynamic Text-to-Speech for OTPs to ensure security and flexibility. Custom audio files are available for promotional voice broadcasting services.

Secure Every User Interaction

Don't let SMS failures cost you users. Add Voice OTP today.

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Secure & Accessible Voice OTP Solutions