Voice Calls API - Overview

Dexatel’s Voice Calls API enables programmatic initiation of live, two-way phone calls via a simple API and real-time audio streaming over WebSocket. Designed as a foundational layer for voice-enabled applications, this feature allows businesses to test and explore direct outbound calling with real-time interaction between a caller and recipient.

Key Features

• Two-Way Calling via API: Initiate outbound phone calls to any valid phone number and enable real-time conversation.
• Real-Time Audio Streaming: Send and receive audio packets via customer-provided stream_url using G.711 A-Law (PCMA), 8kHz, mono.
• No Setup Limits: Designed to support both small-scale testing and large-scale traffic.
• Basic Usage Reporting: Get call ID, duration, and cost after each completed call.
• Flexible Caller Number Options: To use a static Dexatel-owned number associated with your account, contact customer support to enable and configure it for your account.

How It Works

1. Initiate Call You send a request to the API with:
   to: [recipient phone number]
stream_url: [your WebSocket endpoint]
2. Call is Connected Dexatel initiates an outbound voice call to the recipient.
3. Real-Time Streaming Bi-directional audio is streamed over the stream_url via WebSocket using G.711 A-Law (PCMA). You can send and receive audio packets in real time.
4. Call Completion Once the call ends (either the recipient hangs up or max duration is reached), the system returns:
   • Call ID
   • Duration
   • Cost

Please refer to the API References section for additional details.

Benefits

• Simple Integration: Initiate real-time voice interactions with just a few parameters.
• No Hardware or SIP Setup: WebSocket-based audio makes it easy to integrate with existing apps or cloud infrastructure.
• Alpha-Ready for Exploration: Ideal for teams looking to experiment with voice automation, outbound call flows, or AI/IVR-like prototypes.
• Custom Caller Numbering: Associate Dexatel-provided numbers to establish brand identity on outbound calls.

Example Use Cases

• Call Center & Contact Center Platforms Integrate Dexatel’s Voice API to programmatically initiate outbound calls for agent–customer routing, queue handoffs, or automated call flows—paving the way for scalable cloud-based contact solutions.
• Customer Engagement & Marketing Automation Tools Enhance omnichannel workflows by introducing a "Call Now" action within a campaign. Trigger real-time phone calls to users as part of promotions, surveys, or time-sensitive announcements.
• Outbound Sales Enablement & Dialer Systems Use the API to power automated outbound calls, localized call attempts, or auto-dialing based on real-time CRM triggers—such as form submissions or scheduled follow-ups.
• Voice-Powered Notifications Push dynamic, real-time updates via phone calls—such as fraud alerts, appointment confirmations, or delivery notifications—using your own logic and audio streamed through WebSocket.
• Interactive Voice-Based Surveys Initiate calls that play pre-recorded or dynamic audio prompts and collect user responses through return audio—enabling new ways to gather feedback or conduct automated interviews.

Dexatel’s Voice Calls API provides a simple, scalable way to initiate two-way voice conversations—powered by real-time WebSocket audio and direct API control. As part of our evolving voice infrastructure, this early release lays the groundwork for future voice automation, contact center integrations, and real-time communication flows.

Have questions or need help integrating? Contact our team at [email protected] — we’re happy to assist!