8+ Best AI Chatbot APIs [2025]

Is your audience growing past your ability to respond to individual inquiries? Do you see engagement drop offs when your users speak to a chatbot rather than a real person? 

It’s important to connect with your audience and to create systems to enhance user engagement, but large-scale, personalized interactions can be difficult without the right tools. That’s where AI chatbot APIs come in. These AI tools can help developers provide users with a dynamic, helpful first point of contact. 

Let’s explore AI chatbot APIs so you can determine what AI technology may be right for your platform.

What are AI Chatbot APIs?

Chatbots engage in simulated conversations with human users, often for customer service-related purposes. Not all utilize AI technology, but many chatbots use AI’s natural language processing (NLP) due to its increased ability to understand customer inquiries and to respond appropriately. 

AI chatbot APIs are application programming interfaces that allow developers to add artificial intelligence-powered conversational capabilities into their applications, websites, or services. 

These APIs provide a way to access the functionality of chatbots, which are designed to simulate human-like conversations with users–without the need for extensive machine learning expertise or developer resources to build the underlying AI models from scratch.

Who Are AI Chatbot APIs For?

Developers can deploy AI chatbots to serve a variety of functions for a broad range of organizations. In sales, chatbots can function as shopping assistants to serve customers and close sales in real time. They can find products, provide personalized recommendations, or help customers complete their purchases within the chat itself.

Chatbots can also be used to fulfill important customer service roles. This is one of the most widespread use cases, allowing organizations to delegate the task of dealing with frequently asked questions and sorting through inquiries before passing more complex issues on to human customer service agents.

Chatbots are a useful tool for increasing and streamlining user engagement. If you’re looking for more ways to engage with your users, consider an AI chatbot API like Tavus. Tavus can help you interact with your audience using a digital clone of yourself or a stock avatar to individually speak to your users. 

How Do AI Chatbot APIs Work?

Pre-AI chatbots were sort of like FAQs, only more interactive. They were programmed with a limited set of common questions and prepared answers, meaning they could not answer questions that hadn’t already been predicted.

AI chatbots, on the other hand, use machine learning and deep learning to expand their knowledge base as they interact with users. They utilize large language models (LLMs), which use nodes and connections between words to determine the words most likely to come next in a sequence (or in response to inquiries). LLMs weigh and re-weigh the relationships between all the words they know to understand the meaning of user questions and to determine the best answers to those questions.

The Best AI Chatbot APIs

If an AI-powered chatbot API sounds like the public-facing AI tool your platform needs, several companies offer APIs that can help you add an AI chatbot to your app.

1. Tavus API

Tavus offers the best AI chatbot API for developers looking to build human-like conversational interfaces. Through digital twin technology, Tavus enables real-time conversations with AI avatars that replicate facial expressions, lip movements, and natural speech, directly within your platform. 

Developers can use this feature for automated support, onboarding, or customer communication. The novel experience of speaking to a humanlike avatar, instead of a typical text-based chatbot, creates an immersive experience that increases user engagement. 

While other APIs offer custom avatars, Tavus is by far the most realistic, making it the best choice for building next-level conversational experiences.

Features:

• Dynamic, three-dimensional facial scenes: Tavus utilizes a novel approach to AI video generation, using neural radiance fields (NeRFs) to create videos with unprecedented realism and customization.
• Lip sync and dubbing APIs: Users can dub videos in foreign languages and match voice and lip movements to maintain realism.
• Commitment to privacy and security: Tavus employs a suite of safety checks and handles these processes on behalf of the end user.
• Real-Time Conversations: Enable lifelike, human-like chat experiences through real-time AI avatars.
• Seamless Integration: Easily embed conversational avatars directly into your platform or app.
• Scalable API: Supports multiple avatars and interactions.

Pricing:

• Free: $0
• Starter: $39/mo
• Growth: $375/mo
• Enterprise: Contact Tavus sales team for pricing

Learn how you can integrate the power of video today. 

2. IBM Watsonx Assistant

IBM’s conversational AI platform, Watsonx Assistant, allows developers to build their own branded chatbot, or assistant, and integrate it with their device, app, or channel. The assistant connects to an organization’s customer engagement resources, smoothing the problem-solving process for customers and organizations.

Features:

• Agent Assist: Watsonx Assistant helps automate repetitive questions and provide human agents with information to help them respond to complex inquiries more quickly.
• Integration: The API allows for seamless integration of communication channels, systems, tools, and processes.
• Visual Builder: Even if you don’t know how to code, you can use the API’s visual builder to train your chatbot with templates or questions and launch it easily.
• Voice Options: Watsonx Assistant offers clear and friendly voice generation to offer customer service over the phone.

Price: IMB offers the Lite plan for free, the Plus plan for $140/month, and the Enterprise plan with pricing based on your team size and use case.

• Lite plan: Free
• Plus plan: $140/month
• Enterprise plan: Pricing based on team size and use case.

3. Dialogflow

Google’s DialogFlow API allows developers to design and integrate a conversational user interface with their own app or device. The platform can analyze text or audio input from customers and respond through text or synthetic speech. 

DialogFlow offers two virtual service agent services, DialogFlow CX and DialogFlow ES, with different agent types, user interfaces, APIs, client libraries, and documentation.

Features:

• Generative AI Agent: The Vertex AI Agent Builder and DialogFlow allow users to build AI agents that match their brand by connecting user webpages and documents to the AI agent for training purposes.
• Visual Flow Builder: Interactive flow visualizations allow for quick and easy work and collaboration.
• Omnichannel Implementation: Agents can be built once and integrated across platforms with a single deployment.
• End-to-End Management: Accomplish all management tasks, including analytics, experiments, and bot evaluation inside Dialogue without having to turn to other custom software.

‍Price: Pricing is based on particular use cases, varying by characters, time, or count. See product details for more information.

4. Microsoft Bot Framework

Microsoft Bot Framework is an open-source AI toolkit that allows developers to build and connect AI chatbots that can communicate with customers in natural ways for their own platforms. This API even allows developers to connect their bots to social media channels.

Features:

• Open and Extensible: Microsoft Bot Framework utilizes an open-source software development kit (SDK) and allows for bot application across channels and platforms.
• Azure Cognitive Services: Bots speak, listen, understand, and learn from customers through Azure Cognitive Services, which allows bots to continuously adapt and grow through machine learning and natural language experiences.
• Data Ownership: Users control their own data and can use that data to build an AI experience that enhances their brand.
• Comprehensive Toolkit: Microsoft Bot Framework offers various tools and services, including a visual designer and web chat control.

‍Price: Pricing varies based on region, channel, and messaging options.

5. Rasa

Rasa is an open-source AI application-building platform that offers chatbot and voice assistant services. Its API allows users to train models, manage conversations, and interpret user messages. 

Features:

• Customer Support Automation: When connected to an organization’s customer relationship management (CRM) tool, Rasa can process and recognize customer requests and create new cases, provide conversation details, and assign those cases to appropriate support teams.
• Survey Collection Bot: Organizations can use Rasa to create chatbots that collect surveys to automate data collection and analysis.
• Event-Driven Notifications: When paired with the Slack API, Rasa can recognize and create workflows and notifications for events.
• Secure Authentication: Rasa uses API keys, which are stored in Pipeline when connected to Rasa for easy and secure authentication.

Price: 

• Developer Edition: Free
• Growth Package: Starts at $35,000
• Enterprise: Custom pricingRasa provides free access for the Developer Edition; the Growth package starts at $35,000, while those looking for the Enterprise package should contact the sales team for pricing information.

6. Wit.ai

The Wit.ai API allows developers to create apps and devices that communicate with humans conversationally by processing and understanding natural language input via speech or text. The bots created with wit.ai interact on messaging platforms and learn through every interaction with humans.

Features:

• Open to All: Wi.ai provides a free platform for users to create and test chatbot-based natural language experiences.
• Large Language Base: Since chatbots and assistants learn with every new interaction, wit.ai chatbots already have a growing base of 132 languages they understand, providing access for users around the world.
• Community Growth and Development: Valuing growth through collaboration, wit.ai provides developers with access to their community of fellow users, allowing developers to share and leverage community knowledge.
• Voice-Controlled Tasks: Wit.ai bots can understand and execute voice commands related to smart homes.

‍Price: Wit.ai is free for both personal and commercial use.

7. OpenAI API

The OpenAI API allows developers to access OpenAI’s machine learning models for nearly any English-language task. OpenAI’s Assistant API allows developers to create AI chatbots that can provide customers with personalized experiences.

Features:

• Varied Inputs: OpenAI models can respond to text, image, and audio inputs from users.
• AI Model Fine-Tuning: Developers can train models to match their particular use cases.
• Playground: Users can explore OpenAI’s models in the Playground without knowing code.
• Complex Task Completion: Chatbots created through the Assistant API can accomplish complex, multi-step tasks.

‍Price: Users pay only for what they use. Various models include ChatGPT-4, DALL-E, Whisper, and TTS.

8. ApiAI

Managed by DialogFlow (mentioned above), API.AI allows developers to integrate speech recognition and natural language processing, allowing for the use of voice commands and integration with dialogue scenarios for specific agents. 

Features:

• Brand Voice Matching: Chatbots provide unique conversational experiences based on brand voice.
• Speech Recognition: API.AI chatbots can understand and respond to commands given via voice input.
• Voice Activity Detection: The presence or absence of human speech can be detected through Voice Activity Detection (VAD).

‍Price: DialogFlow doesn’t list pricing information online.

8. BOTlibre

Developers can use the open-access BOTlibre API to build and train AI chatbots for personal or commercial use. Their goal is to create an open and safe community of AI chatbot developers.

Features:

• Open Access: BOTlibre provides a wide range of free, open-access features.
• Multilingual: BOTlibre’s API is language-independent, meaning it supports any language.
• Social Media Integration: BOTlibre’s chatbots can be integrated with over 12 social and chat platforms without additional development.
• Easy Bot Creation: Users can create bots with one click using BOTlibre’s library of bot templates.

Price: 

• Basic package: $4.99/month or $49.90/year
• Premium: $19.99/month or $199.90/year
• Enterprise: $49.99/month or $499.90/year

Leverage the Power of AI Chatbot APIs 

Chatbots provide platforms the opportunity to streamline and enhance user interactions. With the power of AI, many chatbots can offer the additional benefit of learning and replicating your team’s voice to add realism to the user experience. 

However, AI video can be another powerful tool for engaging with users, and Tavus’s chatbot APIl, as part of the Tavus ecosystem, can help you leverage the power of video for your platform. The Tavus API offers additional benefits, including individual personalization of pre-recorded videos, lip syncing and dubbing to reach a wider audience, and white-glove developer support.

Whether you think chatbots or AI-personalized videos will better fulfill your application’s needs or you plan to integrate both to broaden your reach, Tavus API can help enhance user engagement quickly and easily.

Ready to integrate the power of a humanlike chatbot into your application? 

Get started with Tavus