Real-time call transcription demo with speech-to-text API

Real-time transcription is becoming a must-have for applications that handle voice. Whether you're building support tools, voice analytics, or AI training pipelines, capturing what’s said on a phone call —in the moment— unlocks huge value.

With the speech recognition market expected to exceed $50 billion by 2030, now’s the time to add voice intelligence to your stack.

A speech-to-text API lets you convert spoken language into readable, structured text. Paired with the Telnyx Voice API, you can place and receive phone calls, and transcribe them live as they happen without needing deep telecom knowledge.

Telnyx gives developers full control over call flows, ultra-low latency for real-time performance, and global reach with a built-in carrier network. Everything runs over simple APIs with clear documentation.

👉 Watch the demo to see it in action and learn how to build live call transcription into your product.

What is in the demo?

In this video demo, we walk through the full set-up. You’ll see how to go from zero to live call transcription in minutes. Here is what we cover:

1. Setting up your account
2. Buying a number
3. Setting up your Telnyx Voice API application
4. Where to test your webhooks (spoiler: webhook.site)
5. Making a live phone call with API commands
6. Transcribing that call in real time using the Telnyx speech-to-text API
7. Reviewing developer resources to help you get started

To follow along, you just need:

• A Telnyx account

During setup, you’ll grab two things (we show exactly where to find them in the video):

• Your Application ID from your Voice API application
• Your API key from the Telnyx portal

We show each of these steps in the demo so you can pause, copy, and test as you go.

Developer resources

1. Get started
2. Dial a number with the Voice API
3. Live transcription with Speech-to-Text API