Sista AI vs Vapi
AI Voice and Phone
Sistava vs Vapi
Vapi is a developer platform for building voice AI agents. Engineers wire up speech-to-text, an LLM, a voice, telephony, and tool calls through one API and SDKs in TypeScript or Python, then ship agents that book appointments, qualify leads, run reception, or handle outbound calls. Vapi handles the orchestration, latency, interruption handling, and tool routing that make voice agents feel real, and integrates with Twilio, Vonage, and SIP for actual phone numbers.,Vapi is sold to product and engineering teams that are building voice into their own product, not to non-technical buyers who want a finished agent. The pricing reflects that: $0.05 per minute platform fee plus separate metered costs for STT, LLM, TTS, and telephony, with real production deployments landing at $0.23 to $0.33 per minute.
Profile
- Pricing
- Pay-as-you-go: $0.05 per minute platform fee, plus separate metered costs for STT, LLM, TTS, and telephony. True total is typically $0.23 to $0.33 per minute in production.
- Founded
- 2023, San Francisco
- Funding
- $70M+ total. $20M Series A in Dec 2024 led by Bessemer Venture Partners, then $50M Series B led by Peak XV Partners at roughly $500M valuation. Backers include Y Combinator, AI Grant, Abstract Ventures, Saga Ventures, Michael Ovitz.
- Focus
- Developer platform for building production voice AI agents on the phone and web. Abstracts orchestration of STT, LLM, TTS, telephony, and tool calling into a single API and SDK.
Why Sista AI
Vapi is infrastructure for engineers building voice agents. Sistava is a workforce: you hire a named AI Employee with a role and a plan, not a voice pipeline you have to assemble.,Vapi is the right answer if your product needs a phone agent and you have engineers to wire one up. Honestly, for that exact problem, it is one of the best tools available, and we are not trying to compete.,Pricing models do not even match. Vapi is per-minute metered (typically $0.23 to $0.33 all in) plus four to six provider contracts. Sistava is a flat monthly plan with a published number on it.,Vapi ships when you ship. Setup involves selecting models, tuning prompts, latency tuning, interruption handling, telephony wiring, tool definitions. Sistava ships today: hire the role, watch work appear on a board.,If voice is your wedge, build on Vapi. If voice is one capability inside a broader AI workforce you need now, Sistava covers more ground in one place, even if the voice surface is narrower.
Feature Comparison
| Feature | Vapi | Sista AI |
|---|---|---|
| Developer platform for voice agents | Named AI Employees with a role | |
| Product engineers building voice into their product | Founders and small teams | |
| $0.05/min platform + metered STT/LLM/TTS/telephony | Free + Personal plan | |
| $0.23 to $0.33 per minute typical | Flat plans, no per-seat | |
| Per-minute rates published, true cost depends on stack | ✓ | |
| Engineering project, days to weeks | Same day, no engineering | |
| Best-in-class voice infrastructure | Voice via integrations, not the focus | |
| Native via Twilio, Vonage, SIP | Via integrations | |
| Your team owns latency, interruption, barge-in tuning | Handled by us | |
| You define tools and HTTP endpoints | Built into each AI Employee | |
| TypeScript and Python SDKs, hosted dashboard | Not the model | |
| BYO STT, LLM, TTS providers | We pick the best model per task | |
| Build them yourself on the platform | Hire all three | |
| Your application owns workflow state | Kanban board per employee | |
| Engineering teams shipping voice as a feature | Non-technical founders and small teams |