Frequently Asked Questions

Is Vapi right for my usecase?

If you are a developer building a voice AI application simulating human conversation (w/ LLMs — to whatever degree of application complexity) — Vapi is built for you.

Whether you are building for a completely “turn-based” use case (like appointment setting), all the way to robust agentic voice applications (like virtual assistants), Vapi is tooled to solve for your voice AI workflow.

Vapi runs on any platform: the web, mobile, or even embedded systems (given network access).

Sounds good, but I’m building a custom X for Y...

Not a problem, we can likely already support it. Vapi is designed to be modular at every level of the voice pipeline: Text-to-speech, LLM, Speech-to-text.

You can bring your own custom models for any part of the pipeline.

If they’re hosted with one of our providers: you just need to add your provider keys, then specify the custom model in your API requests.
If they are hosted elsewhere: you can use the Custom LLM provider and specify the URL to your model in your API request.

Everything is interchangeable, mix & match to suit your usecase.

Why is Vapi best in class?

Vapi solves problems of orchestration and call quality that dramatically improve the experience of your users. We’ve built extremely low-latency, highly intelligent steps that work with multiple model providers.

The vast majority of cost in running your application will come from provider cost (Speech-to-text, LLM, Text-to-speech) direct with vendors (Deepgram, OpenAI, ElevenLabs, etc) — where we add no fee (vendor cost passes-through). These would have to be incurred anyway.

Vapi only charges its small fee on top of these for the continuous maintenance & improvement of these hardest components of your system (which would have costed you time to write/maintain).

No matter what, some cost is inescapable (in money, time, etc) to solve this challenging technical problem.

To learn more about Vapi’s pricing, you can visit our pricing page.

Is it going to be hard to set up?

No — in fact, the setup could not be easier:

Web Dashboard: It can take minutes to get up & running with our dashboard.
Client SDKs: You can start calls with 1 line of code with any of our client SDKs.

For more advanced features like function calling, you will have to set up a Server URL to receive and respond to messages.

How is Vapi different from other Voice AI services?

Vapi focuses on developers. Giving developers modular, simple, & robust tooling to build any voice AI application imaginable.

Vapi also has some of the lowest latency & (equally important) highest reliability amongst any other voice AI platform built for developers.

Can we achieve latency of around 800 milliseconds?

Yes, Vapi is designed to achieve low latency, typically around 800 milliseconds for end-to-end voice processing. Our infrastructure is optimized for real-time communication, and we continuously work to minimize latency through various optimizations in our pipeline.

Do you offer competitive per-minute pricing if we commit to a consistent monthly volume?

Yes, we offer volume-based pricing discounts for customers with consistent monthly usage. The more minutes you commit to, the better the per-minute rate. We’re happy to discuss custom pricing plans based on your specific volume requirements and use case.

Can your platform handle high levels of concurrency, ideally between 100 to 500 sessions daily?

Absolutely. Our platform is built to handle high concurrency, and 1000+ concurrent sessions is well within our capacity. We’ve designed our infrastructure to scale horizontally, ensuring reliable performance even during peak usage periods. For enterprise customers with specific scaling needs, we can discuss custom solutions.

How do you handle PII and PHI securely?

We implement multiple layers of security for PII and PHI:

End-to-end encryption for all data in transit
Secure storage with encryption at rest
Strict access controls and audit logging
Regular security assessments and penetration testing
Data minimization practices
Secure data deletion protocols

All data handling practices are documented in our security policies and compliance frameworks.

Do you support white-labeling?

Yes, Vapi is a API-first platform. This means can bake it in your product without using Vapi branding.

Do you support on-premise deployments?

Yes, we support on-premise deployments for large Enterprises.

Do you support multi-tenancy?

Yes, Vapi is a API-first platform. The integration model of multi-tenancy is similar to Stripe where your application logic will take care of it.