TL;DR — Summary
Voice verification in 4 steps
- 01
Request
Your system calls our API with the user's phone number.
- 02
Call
Our platform automatically calls the user.
- 03
Code
Interactive voice response reads the verification code 2 or 3 times.
- 04
Confirmation
Your API receives a webhook confirming delivery.
Comprehensive Voice OTP
Instant Delivery
Call initiated in under 2 seconds after the API request.
Built-in Anti-fraud
Invalid number detection and automatic abuse blacklisting.
Customized TTS
Choose the voice, speaking speed, and number of code repetitions.
Automatic Fallback
Configure: if SMS fails in X seconds, trigger a voice call.
National Coverage
Works for mobile and landline phones throughout Brazil.
Instant Webhooks
Real-time notifications on call status (answered, busy, etc.).
What our customers say
about our services
"Voice OTP reduced our verification costs by 25%. A lifesaver fallback when SMS experiences carrier latency."
Reynaldo Gianecchini
Rio Grande do Sul - RS
"Our older users praised the clear automated phone calls speaking the numerical token slowly."
Ana Paula Arósio
São Paulo - SP
"With active answering machine detection, we avoid wasted billing on voicemail drops. Great optimization."
Thiago Rodrigues
São Paulo - SP
"The automatic SMS fallback trigger was configured via webhooks in minutes. Exemplary developer UX."
Alinne Moraes
Minas Gerais - MG
"Fast call-based verification that works flawlessly even for landlines in rural municipalities."
Marcello Antony
Mato Grosso - MT
"End-to-end TOTP encryption and sanitized logs in full compliance with ANATEL and LGPD guidelines."
Cláudia Abreu
São Paulo - SP
"Stable 2FA delivery. The average time for the call to connect and the user to verify is only 12 seconds."
Fábio Assunção
São Paulo - SP
"Excellent local TTS speech engine in Brazilian Portuguese that ensures maximum comprehension rates."
Carolina Dieckmann
Rio Grande do Sul - RS
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Add Voice Verification
An extra layer of security for your users. Free sandbox credits to test.