33%
cheaper phone numbers
The math: Synthflow's voice engine alone runs $0.09/min, and their full stack reaches $0.15–0.24/min. Kadeno's telephony is $0.010/min with $0 platform fee. Add your own AI at ~$0.02/min and your total is $0.030/min — less than a quarter of Synthflow's rate.
Pricing
Side-by-Side Comparison
| Kadeno | Synthflow AI |
|---|
| All-in per minute | $0.010 + your AI | $0.15–0.24/min |
| Phone number | $1.00/mo | $1.50/mo |
| Platform fee | $0 | Varies by plan |
| Concurrency | Included | $20/concurrent call/mo |
| Model choice | Any model, any provider | Synthflow's selection |
Cost at Scale
10,000 Minutes/Month
| Kadeno + Own AI | Synthflow AI |
|---|
| Per-minute charges | $100 | $1,500–2,400 |
| Platform fee | $0 | Varies |
| AI (your own pipeline) | ~$200 | Included in rate |
| Numbers (10) | $10 | $15 |
| Total | ~$310 | $1,515–2,415+ |
When Kadeno Wins
Choose Kadeno when
- You have your own AI — If you're running STT, LLM, and TTS yourself, Kadeno gives you the phone line without paying for a bundled AI stack you don't need.
- Concurrency matters — Synthflow's concurrency fees ($20/slot/mo) add up fast. Kadeno has no concurrency limits or fees.
- Developer control — Kadeno streams raw audio to your endpoint. You own the call logic, the prompts, and the models.
- Cheaper numbers — $1.00/mo vs $1.50/mo. Small per number, meaningful at scale.
Choose Synthflow AI when
- No-code deployment — Synthflow's visual builder lets non-technical users create and deploy voice agents without writing code.
- You need everything bundled — If you don't have an AI pipeline, Synthflow gets you a working agent faster.
- Built-in integrations — CRM connectors, appointment booking, and white-label options are built in.
Have your own AI? Pay for telephony, not a bundled stack.
$0.010/min · $1.00/mo numbers · no concurrency fees