13x
cheaper telephony layer
50%
cheaper phone numbers
$840+
saved per 10k minutes
Key difference: Vapi bundles STT + LLM + TTS + telephony into one per-minute rate ($0.13–0.31/min). Kadeno provides only the telephony layer ($0.010/min) — you bring your own AI. If you already have an AI engine, Kadeno is dramatically cheaper.
Pricing
Side-by-Side Comparison
| Kadeno | Vapi |
|---|
| Telephony (inbound) | $0.010/min | ~$0.015/min (bundled) |
| STT | Bring your own | $0.015–0.04/min |
| LLM | Bring your own | $0.003–0.08/min |
| TTS | Bring your own | $0.015–0.04/min |
| Phone number | $1.00/mo | ~$2.00/mo |
| Platform fee | $0 | Varies |
| All-in per minute | $0.010 + your AI | $0.13–0.31 |
Cost at Scale
10,000 Minutes/Month
| Kadeno + Own AI | Vapi |
|---|
| Telephony | $100 | ~$150 |
| AI (STT+LLM+TTS) | ~$200 (your cost) | $1,000–2,950 |
| Numbers (10) | $10 | $20 |
| Total | ~$310 | $1,170–3,120 |
When Kadeno Wins
Choose Kadeno when
- You have your own AI — If you're running your own STT/LLM/TTS pipeline, Kadeno gives you the phone line at a fraction of Vapi's bundled cost.
- You want control — Kadeno streams raw audio. You decide what to do with it. No vendor lock-in on the AI layer.
- You're building custom voice experiences — Call analytics, transcription pipelines, IVR systems, and VoIP apps don't need Vapi's agent framework.
- Cost at scale — At 10,000 minutes/month, Kadeno telephony costs $100. Vapi's all-in rate runs $1,300–3,100.
Choose Vapi when
- You want everything bundled — Vapi handles STT, LLM, TTS, and telephony in one API. Less to build, faster to launch.
- You don't have an AI engine — Starting from zero and just want a talking agent on a phone number? Vapi gets you there faster.
- You need built-in agent features — Function calling, knowledge bases, conversation memory, and interruption handling are built in.
Already have an AI engine? Cut your telephony costs.
$0.010/min · $1.00/mo numbers · $0 platform fee