Vobiz vs Vapi: Different Layers of the Stack
Vobiz and Vapi are at different layers of the AI voice stack. Vapi is an AI voice agent orchestration platform — it manages LLM selection, TTS, STT, conversation flow, and the agent API. Vobiz is telephony infrastructure — it provides the SIP trunk, phone numbers, outbound calling, inbound routing, AMD, and real-time audio streaming. They complement each other. Vapi’s recommended way to place and receive PSTN calls is to connect a SIP trunk from a provider like Vobiz. If you’re evaluating Vobiz as a Vapi telephony provider, that’s the right comparison. If you’re looking to replace Vapi’s orchestration capabilities, Vobiz alone covers different use cases.What each platform does
How they work together
Vapi connects to Vobiz as its SIP trunk provider. Vobiz handles the PSTN connection; Vapi handles the AI agent.When to use Vapi + Vobiz
Use Vapi as your orchestration layer and Vobiz as your telephony layer when:- You want a managed agent API with structured conversation flows, squads, and analytics
- You need to swap LLM and TTS providers without rebuilding your stack
- You want pre-built call analysis and transcript tooling
- Your Vapi deployment needs PSTN calling outside the US (Vobiz covers 130+ countries)
- You need India 140-series numbers for TRAI-compliant A2P outbound
When to use Vobiz alone
Vobiz handles voice AI without Vapi as the orchestration layer. Use Vobiz directly when:- You are building a custom AI pipeline (your own STT, LLM, TTS, conversation logic)
- You want to mix traditional IVR (XML) with AI segments in the same call
- You are using an orchestration layer other than Vapi (Retell AI, Pipecat, LiveKit, ElevenLabs)
- You need maximum control over audio format, streaming rate, and latency
Example: mixing IVR and AI in one call
After the caller selects support:
Pricing comparison
When using Vapi + Vobiz, you pay Vapi for agent minutes (LLM tokens + TTS + orchestration) and Vobiz separately for telephony minutes and number rental. The invoices are separate.
India support
For India deployments, Vobiz is essential regardless of which AI orchestration platform you choose. Vapi cannot provision Indian numbers or 140-series caller IDs — the telephony compliance layer must come from a provider like Vobiz.