$0.010
per minute, in or out
Any AI
STT · LLM · TTS engine
$1.00
per number per month
How it works: Kadeno provisions a real US phone number, answers inbound PSTN calls, and streams raw audio over a WebSocket to your AI endpoint. Your agent processes the audio, responds, and Kadeno relays it back — all in real time. No TwiML. No XML. One JSON API.
Setup
Three API calls to a working voice agent
- Provision a number —
POST /v1/numbers/purchase gives you a real US phone number in seconds.
- Register your agent —
POST /v1/agents with your AI endpoint URL and endpoint type (WebSocket, OpenAI Realtime, HTTP, or CAIZA).
- Assign the number —
POST /v1/numbers/{id}/assign links the number to your agent. Inbound calls are now routed to your AI.
AI Compatibility
Connect any AI engine
- WebSocket — Stream raw μ-law 8kHz audio bidirectionally. Works with Deepgram, AssemblyAI, or any custom STT pipeline.
- OpenAI Realtime — Native integration with the OpenAI Realtime API. Route calls directly without an intermediary server.
- HTTP — Send audio chunks as POST requests. Your endpoint returns audio to play back.
- CAIZA — Kadeno's default AI engine. Drop-in conversational AI for agents that don't need custom models.
Pricing
Pay only for what you use
| Item | Rate |
|---|
| Inbound voice (PSTN → agent) | $0.010/min |
| Outbound voice (agent → PSTN) | $0.010/min |
| US local phone number | $1.00/mo |
| Toll-free number | $1.15/mo |
| Platform fee | $0 |
When to use Kadeno for voice agents
- You already have an AI pipeline — If you're running Whisper, GPT-4o, or ElevenLabs yourself, Kadeno provides the phone line without bundling AI you don't need.
- You want model flexibility — Switch STT, LLM, or TTS providers without changing your phone number or API integration.
- Cost at scale — At 10,000 minutes/month, Kadeno telephony costs $100. Bundled AI voice platforms run $1,000–3,000+ for the same volume.
- No lock-in — Your call logic lives in your code. Kadeno is infrastructure, not a framework.
Ready to put your AI agent on a real phone line?
Get your number →
$0.010/min · $1.00/mo numbers · any AI engine · $0 platform fee