2025 Vapi AI Review: BEST Voice Agent To Build With?

Vapi is an AI voice agent platform that allows companies to use realistic sounding voice agents to deal with inbound and outbound phone calls. In 2020, Vapi launched as Superpowered, an AI-powered notetaker for meetings, but in 2023 and with $2.1 million in funding from Kleiner Perkins, Y Combinator and Abstract Ventures, the company pivoted to today’s AI voice agent platform. And in December 2024, Vapi announced it had raised a further $20 million led by Bessemer Venture Partners.

So what exactly does Vapi AI do?

Vapi AI is an advanced voice AI platform designed to provide realistic and natural-sounding voice interactions for enterprises. It offers AI-powered voice agents that cater to various sectors, including customer service, sales teams, and consumer-facing companies. The platform offers multi-language support and allows seamless integration with various applications for daily use cases.

Vapi AI’s engineering team, led by Nikhil Gupta and Jordan Dearsley, have now built a mature platform which allows companies to deploy voice-enabled assistants with minimal human intervention. With its advanced voice recognition and natural language understanding, Vapi AI enables businesses to handle inbound calls, outbound calls, and AI phone agents efficiently. The platform also provides extensive customization options to fit specific needs, making it an ideal choice for companies looking to improve operational efficiency.

Most importantly, the voices sound more human-like than ever before. Neuphonic is proud to be a text-to-voice provider on Vapi and you can test Neuphonic’s latest AI voice models with a first message once signed up.

How do voice agents work?

Voice AI agents use generative voice models to interpret and respond to human speech. These models rely on natural language processing and natural language understanding to enhance user experience. The AI model processes voice interactions in real-time, allowing businesses to automate customer support and appointment booking.

To enable your agents to provide the best contextual responses, businesses can setup a knowledge base from documents, PDFs or file connection via API. Team members can add notes to enable the voice agent to answer customer questions in the most on-brand way.

Vapi AI integrates with various platforms, such as web applications and calendar apps, enabling companies to manage phone calls efficiently. The voice assistant can also support food ordering and AI-driven call logs for tracking conversations. The best part? AI-powered voice agents continuously learn and improve through conversational AI.

Do phone calls using Vapi sound realistic?

Vapi AI stands out due to its advanced voice recognition, ensuring voice interactions sound human-like. Unlike other platforms such as Retell AI, Bland AI, and Lindy Voice Agents, Vapi AI delivers conversational voice agents with natural intonation and expression. This enhances the voice AI strategy for businesses, making it the world’s default interface for customer interactions.

These agents are powered by partners like Neuphonic. In a recent experiment, Neuphonic ran ~100 voice samples through competitors like Cartesia, ElevenLabs and ElevenLabs Flash. Across different input lengths and contexts, Neuphonic came out top in terms of voice realism and production stability.

With white-labeling platforms, businesses can customize voice operations to reflect their brand identity. Vapi AI’s AI phone agents offer free credits for testing, allowing companies to explore the platform before committing to monthly fees.

Companies That Benefit by Using Vapi AI’s Platform and API

Vapi AI serves various sectors, including:

• Customer Service & Support: Automating inbound and outbound calls for better customer engagement and happiness

• E-commerce & Food Ordering: AI-driven solutions for handling orders, package tracking, dispatch and realtime customer service

• Healthcare & Appointment Booking: Luma Health and other medical providers use Vapi AI for managing patient interactions

• Sales Teams & Lead Generation: AI voice agents streamline communication with potential customers to qualify leads and reduce operational overhead

• Tech & SaaS Companies: Seamless integration into web applications for an improved user experience

Vapi’s powerful tool allows these types of businesses with unique business problems to spin up phone numbers and have AI agents respond to customers in realtime.

Vapi pricing model

Vapi has a free version that allows businesses to try the platform with $10 worth of credits. After that, Vapi starts at $0.05 per minute for basic functionality, but this cost can increase if you need to use an LLM like ChatGPT to generate responses from transcribed text, or use a telephony provider like Twilio or Vonage. This can increase costs upto $0.13 per minute.

The good news is that to use a higher quality, human-like voice within Vapi, like Neuphonic, there is no extra cost.

At scale, Vapi AI has payment options that include:

• Pay-as-you-go API keys: Ideal for developers working on AI voice applications

• Subscription-based pricing with monthly fees: Perfect for enterprises requiring concurrent calls

• Enterprise-level solutions: Custom pricing for large-scale implementations with a 24/7/365 Slack channel and other benefits

Users can access their Vapi account through the Vapi dashboard, where they can manage call recordings, AI models, and voice interactions.

Does Vapi Have Any Competitors?

While Vapi AI is a leading developer platform, it does have competitors, such as:

1. Lindy: Lindy voice agents offers a more user-friendly user interface for non-developers. Lindy also offers agents that can update your CRM, do follow-up calls, manage tasks, assist with sales pipeline, enable compliance and schedule meetings

2. Synthflow: Synthflow competes on cost with Vapi, offering a flat-pricing business model at $0.13 per minute. For this you get ElevenLabs integration included as well as transcription and high concurrency

3. LiveKit: LiveKit is built on WebRTC and allows businesses to build realtime video and audio communication solutions. LiveKit also has a free tier which offers 100 concurrent participants and 5,000 connection minutes per month but paid plans for more concurrency and minutes start from $50 per month. It offers integrations with AI chatbots like Google Gemini

4. Retell: Retell AI ensures compliance with industry standards like HIPAA and SOC 2 Type II and allows for single and multi prompt AI voice agents with support for custom LLMs and 19 languages

5. Pipecat: Pipecat is an open-source Python framework for building conversational voice agents. It is less scaleable than competitors like LiveKit but it has an active community for developers looking for ultimate flexibility

6. Vocode: Vocode is another open-source voice AI platform that builds voice agents on top of LLMs. However it is more difficult to use for non-technical users

Should I use Vapi for my applications?

If your business requires AI-powered voice agents with advanced features and seamless integration, Vapi AI could be a great platform to help you in the final step of optimizing customer engagement. The platform is known for:

• Easy implementation for small and medium sized businesses

• A rich developer ecosystem with helpful documentation and support on Discord

• Multiple languages and dialects supported thanks to TTS underlying models like Neuphonic

• Support for white-labeling platforms to customize branding

• Call recordings and call logs for tracking voice operations

• Pricing that starts at cheaper than competitors for potential cost savings

Final verdict

Vapi AI is an ideal choice for companies seeking a powerful voice AI platform. Customers around the world from London to San Francisco are using Vapi to implement an advanced voice AI strategy that aligns with their specific needs. With features like API keys, code tutorial support, and extensive voice AI applications, Vapi AI sets the standard for conversational AI in 2025.