There are numerous API providers in the chatbot landscape, with the majority focusing on Natural Language Processing (NLP) and Natural Language Understanding (NLU).
It is a crucial decision to make, as this will affect the most important aspect of a conversational interface. We compared the top five natural language processing platforms and their features.
Natural Language Platforms (NLP) comparison
We compared the top 5 specialized NLP platforms, along with their key features. We created a straightforward calculator to estimate the approximate cost of each vendor using pay-as-you-go pricing systems.
Platform | Best for | Allow Import/Export Model | Limits for API Calls |
---|---|---|---|
Azure CLU | Enterprise apps | ✅ | FREE: 10k queries/month, 5 queries/second PAID: pay per transaction |
Google DialogFlow ES | Multi-channel chatbots | ✅ | FREE: 180 requests/minute (7.5M/month) PAID: Scales with usage |
Amazon Lex | AWS ecosystem integrated apps | ❌ | Speech: 15 seconds Text: 1024 characters |
IBM watsonx Assistant | Enterprises that prioritize security | ✅ | FREE: 1k API queries/month PAID: Unlimited |
Wit.ai | Simple/prototype applications | ✅ | Unlimited with rate limits |
Although we prioritized specialized conversational language understanding and natural language processing platforms in this article, there is also a second type of NLP tool you can use: general large language models with NLP capabilities. We developed a feature comparison table for traditional NLP platforms and LLMs, enabling you to select the one that best suits your business needs.
Feature | Traditional NLP Platform | LLM API |
---|---|---|
Convsersation flow | Predefined and structured | Flexible and context-aware |
Input type handling | Precise intent classification according to training data | Unstructured, complex user inputs |
Training requirements | Example phrases and structured training data | Already trained, just fine-tune to your needs |
Setup complexity | Higher initial setup, intent/entity modeling required | Lower setup, prompt-based configuration |
Customization approach | Training phrases, entities, conversation flows | Prompt engineering, fine-tuning |
Integration | Built-in messaging platform connectors | Usually custom integration |
Enterprise features | Built-in conversation analytics and user management | Requires additional tooling for analytics and user management |
Top 5 specialized NLP platforms
1. Azure Conversational Language Understanding (CLU)
The next generation of Language Understanding (LUIS), Azure Conversational Language Understanding (CLU), uses machine learning models to increase accuracy. With multilingual support in 96 languages, CLU provides superior semantic understanding while using less training data than conventional methods. Projects can be trained in a single language and instantly anticipate intents and entities in other languages.
CLU is a relatively new service with fewer community resources than more established platforms, and it necessitates migration from the deprecated LUIS platform. Some advanced capabilities that were available in LUIS, such as nested ML entities, are not supported by CLU.
It is ideal for enterprise applications that require advanced intent recognition and multilingual support, as well as for businesses currently using LUIS that must migrate before its retirement date, October 1, 2025.
2. Google Dialogflow
Dialogflow provides tools for building both text- and voice-based conversational agents, with capabilities for speech-to-text and text-to-speech conversion.
It is best suited for applications requiring multi-channel support, such as chatbots and virtual assistants that interact with messaging platforms (e.g., Slack, Facebook Messenger) and voice-based systems (e.g., Google Assistant, Alexa). Dialogflow works well at handling structured data like dates and currencies.
However, it lacks advanced customization features for fine-tuning models and does not offer as many advanced enterprise integration options compared to some competitors.
Google Dialogflow is ideal for developers who need a straightforward, scalable platform with extensive language support.
3. Amazon Lex
Amazon Lex integrates with AWS services, supporting both text and speech, and leverages the same deep learning technology that powers Alexa. Lex is particularly beneficial for developers looking to create conversational interfaces within the AWS ecosystem.
However, Lex lacks out-of-the-box integrations with third-party platforms and messaging apps compared to other platforms, such as Dialogflow. While it provides powerful natural language understanding and speech recognition, it may require additional setup for non-AWS developers.
Amazon Lex is ideal for organizations aiming to develop advanced conversational interfaces for customer service, support, and virtual assistants.
4. IBM watsonx Assistant
IBM watsonx Assistant is best known for its use in enterprise environments, providing advanced NLP capabilities for applications ranging from customer support chatbots to virtual assistants. One of Watson Assistant’s main strengths is its easy integration with various platforms, including websites, mobile apps, and social media.
However, it does not provide intuitive development tools like Google Dialogflow CX’s drag-and-drop Visual Flow Builder, Amazon Lex V2’s guided Conversation Builder, or Azure Language Studio’s no-code custom-text interface. As a result, it does not offer the same degree of flexibility for customizing and training models as some competing services.
IBM watsonx Assistant is ideal for companies across industries that require advanced security, support for multiple languages, and scalability.
5. Wit.ai
Wit.ai offers a free NLP platform that permits commercial use without request limits, though with some rate restrictions. This platform excels in intent recognition, entity extraction, and speech recognition, making it especially effective for voice-based applications. Wit.ai provides an accessible entry point for developers creating chatbots and voice assistants, eliminating the need for initial costs.
While it is a reliable choice for constructing simple NLP applications, it falls short of the enterprise support and integration tools available on larger platforms. Additionally, it lacks ready-made integrations with well-known third-party messaging platforms or enterprise systems.
Wit.ai is ideal for developers of basic NLP applications, startups seeking free solutions, and those focused on speech-to-text and voice-driven apps.
LLMs with NLP powers
Specialized NLP frameworks are crucial for achieving precision, speed, and a comprehensive understanding of linguistic structures while maintaining low computational costs. Conversely, LLMs add complexity for tasks that require context-sensitive responses.
We have provided a brief summary of vendors’ integrated capabilities for NLP tasks. For more details, explore LLM examples to see the various LLM options available and LLM pricing to understand the charges for LLM APIs.
- OpenAI offers refined natural language processing (NLP) features with context windows up to 128,000 tokens through multimodal processing, function calling, text output, and debate. OpenAI is proficient in content generation, complex thinking, and flexible conversational AI.
- Anthropic Claude offers Constitutional AI and reasoning skills for safer, more dependable outcomes. Claude provides advanced natural language processing (NLP) through reasoning, long-context understanding, online search integration, and tool usage. The platform is ideal for applications that require advanced comprehension and responsible AI responses, as it was designed with safety-first principles in mind.
- Google Gemini 2.5 Pro and Flash variants support over 140 languages and feature context windows of up to 2 million tokens, enabling progressive thinking. Gemini offers multimodal comprehension, reasoning, and text production, all while being integrated into the Google environment. The platform works best with Google Workspace integration, multilingual apps, and businesses looking to scale at a reasonable cost.
- Command’s Cohere is an enterprise-focused LLM platform with task-oriented pricing and robust compliance capabilities, specifically designed for corporate applications. The platform provides choices for both on-premises and private cloud deployments, and it enables text generation, embeddings, classification, summarization, and semantic search capabilities. Cohere is ideal for businesses that need complete control over their infrastructure and data for specialized NLP activities.
- Meta Llama offers transparent, fully customizable big language models in a range of sizes and capabilities. The platform enables businesses to adapt and implement models following their needs while supporting text generation, dialogue, and reasoning. Organizations seeking total control over their AI infrastructure and the capacity to modify models for specific use cases are best suited for Llama.
What is the difference between NLP and NLU?
Natural Language Processing (NLP): In the context of artificial intelligence (AI), NLP is the overarching umbrella that encompasses several disciplines that tackle the interaction between computer systems and human languages. From that perspective, NLP includes several sub-disciplines such as discourse analysis, relationship extraction, natural language understanding and a few others language analysis areas. NLP includes:
- Tokenization (breaking down text into words or phrases)
- Part-of-speech tagging
- Named entity recognition (NER)
- Sentiment analysis
- Text generation and translation
Natural Language Understanding (NLU): NLU is a subset of NLP that focuses on reading comprehension and semantic analysis. The combination of NLP and NLU technologies is becoming increasingly relevant on different software areas today including bot technologies. While there are many vendors and platforms focused on NLP-NLU technologies, the following technologies are becoming extremely popular within the bot developer community. NLU includes:
- Intent recognition: Understanding what the user wants to do.
- Entity extraction: Identifying specific pieces of information (e.g., dates, locations, product names).
- Contextual interpretation: Figuring out meaning from ambiguous or unstructured language.
NLP models can handle tasks like:
- text preprocessing
- classification
- summarization
NLU becomes critical when AI needs to interpret and respond intelligently to user queries, especially when the input is ambiguous or lacks structure. Some models include both.
FAQ
Further reading
- Ways NLP & RPA Enable Intelligent Automation
- How to Build a Chatbot: Components & Architecture
- Chatbot vs ChatGPT: Differences & Features

Cem's work has been cited by leading global publications including Business Insider, Forbes, Washington Post, global firms like Deloitte, HPE and NGOs like World Economic Forum and supranational organizations like European Commission. You can see more reputable companies and resources that referenced AIMultiple.
Throughout his career, Cem served as a tech consultant, tech buyer and tech entrepreneur. He advised enterprises on their technology decisions at McKinsey & Company and Altman Solon for more than a decade. He also published a McKinsey report on digitalization.
He led technology strategy and procurement of a telco while reporting to the CEO. He has also led commercial growth of deep tech company Hypatos that reached a 7 digit annual recurring revenue and a 9 digit valuation from 0 within 2 years. Cem's work in Hypatos was covered by leading technology publications like TechCrunch and Business Insider.
Cem regularly speaks at international technology conferences. He graduated from Bogazici University as a computer engineer and holds an MBA from Columbia Business School.
Comments 3
Share Your Thoughts
Your email address will not be published. All fields are required.
Thanks for this comparison! In case you are interested, please not that we recently released a new NLP API called NLP Cloud (nlpcloud.io). It basically does named entity recognition and part of speech tagging. It is using the spaCy Python library under the hood so you can either use pre-trained models and it just works out of the box, or upload your own custom models trained with spaCy. All the small spaCy models are free. Thanks!
Great Guide! Have you heard about https://bothub.it ? It’s a new option for NLU!
That’s a great guide, thank you for your work. I think Natural Language Processing has a big potential as a part as Artificial Intelligence technology. Chatbots are great for many industries, with the most beneficial being Retail. I recently wrote an article on NLP, and I am very optimistic about future of this technology. Everything necessary for this technology is here, the question is in how good it can be. Considering the current state, we will see some major improvement very soon.