VOICE CALLS, YOUR WAY
With Sinch Voice API, developers get everything they need to add calling to their apps — global phone numbers, flexible APIs, and SDKs for outbound, inbound, and in-app calling. Advanced features are on demand, ready whenever you need them.
EASY, MODERN, AND SCALABLE
With Sinch Voice API, developers get everything they need to add calling to their apps — global phone numbers, flexible APIs, and SDKs for outbound, inbound, and in-app calling. Advanced features are on demand, ready whenever you need them.
OUTBOUND CALLS
Start PSTN, SIP, or app-to-phone calls through a simple API — perfect for sending reminders, alerts, or connecting customers with agents.
Start calls with REST
Use local or toll-free numbers in 70+ countries
INBOUND CALLS
Programmable menus make it easy to route calls automatically and get customers to the right team or system.
Support for keypad input (DTMF)
Speech recognition for spoken numbers in IVR menus
Smart routing to apps, agents, or contact centers
REAL-TIME INSIGHTS
Stay on top of every call with live webhooks that send JSON callbacks and integrate directly into your business systems.
Get full lifecycle visibility with call detail records
Export logs for BI, analytics, and compliance
Use multilingual TTS to meet regulatory and customer requirements
WHERE IT WORKS
ALL THE ESSENTIALS
Sinch Voice API is a programmable voice platform that lets applications make and manage calls. It supports outbound and inbound PSTN, SIP, and in-app calling, and adds advanced features like Text-to-Speech (in 115+ languages), IVR menus (with keypad and numerical speech input), call recording, transcription, number masking, and conferencing.
The API follows a request-and-response model:
•Your application sends a command via REST to start or manage a call (e.g., “make a call and play a message”).
•The Sinch platform connects the call across PSTN, SIP, or in-app channels.
•As the call progresses, the platform sends real-time webhooks (callbacks) back to your application (ringing, answered, disconnected, key press, etc.).
•Your application can then decide the next action (e.g., transfer the call, play audio).
Sinch Voice API supports REST APIs, HTTPS, and SIP protocols. It handles PSTN ↔ PSTN, PSTN ↔ SIP, SIP ↔ SIP, App ↔ App, and App ↔ PSTN (WebRTC) call types.
Setup can be done in minutes. To get started, create a Sinch account, get your API keys, and start with test calls to your verified number — no telecom hardware required. For enterprise deployments, onboarding can also be sales-assisted.
The platform offers global reach with local, mobile, and toll-free numbers in 70+ countries and 16,000+ cities. Infrastructure is distributed across five AWS regions to optimize call quality and reliability.
You can extend calls with features like text-to-speech (TTS) in 115 languages, answering machine detection (AMD), call recording and transcription, IVR (DTMF keypad input and speech recognition for numerical input), number masking, call forwarding, conference calling, and real-time audio streaming for AI and analytics.
Yes. The Voice API platform is ISO 27001 certified, GDPR compliant, STIR/SHAKEN compliant (US/CA), and TLS/SRTP encrypted for signaling and media.
Pricing is usage-based with per-minute charges for inbound and outbound calls plus optional rental of local, mobile, or toll-free numbers. Features like recording, transcription, and AMD are billed separately.
Learn how to add calling to your apps with global numbers, flexible APIs, and advanced features like TTS, IVR, and call recording.