Developer API

The Scalable AI Voice API for Next-Gen Applications

Build with confidence. 1000+ voices, 142+ languages, real-time streaming, and industry-leading reliability.

100 free requests/day • No credit card required

Build with Confidence: Speed, Scale, and 142+ Languages

Enterprise-grade infrastructure with 99.9% uptime SLA, global CDN distribution, and the most comprehensive language support in the industry.

<500ms

Average response time

99.9%

Uptime SLA

SOC 2

Compliance ready

Trusted by 3.5m users across 150+ countries

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Key Features

Real-Time Streaming

Sub-200ms first-byte latency for conversational AI and live applications.

Voice Cloning Endpoint

Create custom voice models via API with just 30 seconds of reference audio.

Custom Pronunciation

SSML support and custom pronunciation dictionaries for domain-specific terms.

142+ Languages

Global reach with native-quality voices across 142 languages and regional accents.

Get Started in Minutes

Comprehensive documentation and SDKs for quick integration

Python
import listnr

client = listnr.Client(api_key="your_api_key")

# Generate speech
audio = client.tts.create(
    text="Hello, welcome to Listnr!",
    voice="en-US-neural-male-1",
    output_format="mp3"
)

audio.save("output.mp3")
Node.js
const Listnr = require('listnr');

const client = new Listnr({ apiKey: 'your_api_key' });

// Generate speech
const audio = await client.tts.create({
  text: 'Hello, welcome to Listnr!',
  voice: 'en-US-neural-male-1',
  outputFormat: 'mp3'
});

fs.writeFileSync('output.mp3', audio);

Built for Every Use Case

From telephony to gaming, our API powers voice applications across industries

IVR & Telephony

Build natural-sounding phone systems with 8kHz telephony-optimized output.

Conversational AI

Power chatbots and voice assistants with real-time streaming responses.

Gaming

Dynamic NPC dialogue and accessibility narration for games.

Content Localization

Localize video, audio, and e-learning content across 142+ languages.

Transparent, Volume-Based Pricing

No hidden fees. Pay only for what you use.

Free

$0/month

  • ✓ 100 requests/day
  • ✓ 50+ voices
  • ✓ Standard latency
Get Started Free
Popular

Pro

$99/month

  • ✓ 10,000 requests/day
  • ✓ 1000+ voices
  • ✓ Real-time streaming
  • ✓ Voice cloning
Start Pro Trial

Enterprise

Custom

  • ✓ Unlimited requests
  • ✓ Dedicated infrastructure
  • ✓ Custom SLA
  • ✓ Priority support
Talk to Sales

Frequently Asked Questions

The Listnr TTS API is a RESTful API that converts text to natural-sounding speech. It supports 1000+ voices across 142+ languages, with features like voice cloning, SSML support, emotion control, and real-time streaming for low-latency applications.
Our API is optimized for low latency. Standard requests complete in under 500ms for most text lengths. Real-time streaming is available for conversational AI applications requiring sub-200ms first-byte latency.
The API supports MP3, WAV, OGG, and FLAC output formats. You can specify sample rates from 8kHz (telephony) to 48kHz (broadcast quality) depending on your use case.
Yes! Our voice cloning API endpoint allows you to create custom voice models from audio samples. Clone voices with as little as 30 seconds of reference audio for use across all supported languages.
Rate limits vary by plan. Free tier: 100 requests/day. Pro: 10,000 requests/day. Enterprise: Unlimited with dedicated infrastructure. All plans include burst capacity for traffic spikes.
Yes, we provide official SDKs for Python, Node.js, and REST. Community SDKs are available for Go, Ruby, and PHP. All SDKs are open source and available on GitHub.

Start Building with the AI Voice API

Get your API key in seconds. 100 free requests daily, no credit card required.

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