Top 5 NLP Chatbot APIs to Make Your First Conversational Chatbot

Top 5 NLP Chatbot APIs to make Your First Conversational Chatbot

Now, most of the people know about the chatbot. Before the year 2015, very few people knew about it. But as the Artificial Intelligence or automation become trendy topic then we came to hear about the term Chatbot. A chatbot is a conversational bot or a Chatting user interface(UI) where you are chatting with the computer made bots. It means there is no human intervention. But its true for only NLP chatbot. A simple chatbot is not so smart outside the knowledge base.

In this article, you will know the top 5 NLP chatbot APIs. After reading the entire post, I am sure that you will find your best APIs for making your first conversational chatbot.


But before going further these are the articles I will recommend you to first read for refreshing your mind on chatbot.

What is Chatbot ? : An Artificial Intelligence Insight

Know the Underline Technology behind Artificial Intelligence Chat Bot

Best Artificial Intelligence Chat Bot Development Video Resources

Top 5 NLP Chatbot APIs to make Your First Conversational Chatbot

Why NLP Chatbot, not Simple Chatbots?

You must be aware of types of chatbots. There are two types of chatbots one is Simple and other the NLP Chatbots. A simple chatbot is the basic computer bots. They are the database of questions and answers. When the user asks the questions, then chatbot searches for the question.

If it finds the question then its corresponding answers will be shown to the user. Otherwise, It will show “sorry the question is wrong”, “Type the correct question or other errors”. Therefore its beneficial for small business not for large business.

NLP Chatbots remove the simple chatbot limitation. Since NLP (Natural Language Processing) comes in the category of Artificial Intelligence. Therefore sometimes it is also called as AI Powered chatbot.

When the user asks the question, NLP Chatbot understands the questions and gives the answers. Even when the exact questions are not matched then it will show the suggestions to the requested users.

In addition Questions and answers are also recorded in the database for the futures use. These data are trained to make the efficient chatbot. You can say as the time passes these NLP chatbots learns from previous task upgrade themselves.

What are the purposes of Conversational Chatbot?

Conversational chatbots are useful for the customer interactions in the business. For example, in the e-commerce sector, chatbots are useful to answers the request for the details of the product or service requires the customers.

It can also give product suggestions. There are many other field chatbot integration is going on like chatbots for a lawyer, doctor, student, actor and many more. The main aim of the conversational chatbots is to improve the customer experience and interaction within the businesses.


Top tools for  building the conversational chatbots( Best chatbot API)

Before finding the right tools for creating a chatbot. You have to decide the purpose of the chatbot and on which platforms you want to integrate the chatbot. After all these answers you move to the creation part.

There are various tools for building a fully working NLP chatbot. But in this post, you will know the best tools for creating it. What are their major features?

IBM Watson

From the name you can know it has been developed by the IBM. It is built in such a way that it can nearly understand all the conversational texts typed by the users. In addition, its also learn from the previous interactions.

Recently IBM has moved IBM Watson on the cloud. It has also released the APIs for the chatbot developer. Thus it makes very easy for the user to make a conversational chatbot. IBM Watson is built on Neural Networks. This tool is suitable for chatbots integrating with IBM services.

Integration with other languages

IBM Watson has nearly various programming language SDKs. It has node SDK, Java SDK, Python SDK, iOS SDK as well as Unity SDK.

Platforms Available

IBM Watson understands voice, text, and images. Therefore It will work on any messaging platform that are supporting text, voice, and images.


Currently, it supports only two languages that are English and Japanese.


IBM Watson has currently three plans lite, standard and premium.

Lite Plan: It has a limit of 10000 APIs call per month, up to 5 Workspaces, 100 Intents, and up to 25 Entities. Price is free.

Standard Plan: No limit on APIs call per month. You have to just pay $0.0025 per API call. You can have 20 workspaces, 2000 Intents, and up to 1000 entities.

Premium Plan: Unlimited API calls. You have to contact them manually.

You can know more from their official Website IBM Watson Plans


DialogFlow is supported by Google. It uses entities, intents, and actions with parameters for making a conversational chatbot. DialogFlow has the ability to converts text to speech and speech to text. It also comes with machine learning thus making your model to train.

DialogFlow has also some built in the knowledge base for the casual talks. Thus you don’t have to train the bot for the causal talks intents. All the output you get in the dialog flow is in JSON format. It is suitable for middle-level chatbots.


Programming Language Supported and integration

DialogFlow nearly supports all the languages and SDKs. Android, iOS, Cordova, Javascript,HTML, Node.js, .NET, Unity, Xamarin, C++, Python, Ruby, PHP, JAVA Facebook messenger, slack e.t.c.

Platforms Available

It supports all the messaging platform that support texts and speeches.


As compare to other NLP Chatbot tools DialogFlow support more Languages like English, Chinese, French, Spanish, Russian and many more.


It is freely available and also you can call Unlimited APIs. But only for text. There is a limit for voice integration that is 1000 request per day with maximum 15000 requests per month.

Amazon Lex

Amazon lex is best for building the conversational interfaces for the chatbot using both the voice and text messages. It is used to build a new Natural language chatbot applications. It can also integrate with the existing chatbot application.

There is the best thing I like about Amazon Lex is that it provides NLU(Natural Language Understanding ) and automatic Speech recognization that make it more real life chatbot conversational chatbots.

Programming Language Supported and integration

It supports most of the programming language and SDKs. Java, JavaScipt, Python, C++, Php, Ruby e.t.c are the programming language supported by Amazon lex.

Platforms Available

You can easily integrate amazon lex with Facebook, Slack. There is also an Amazon Lex API which allows you to connect with third-party messaging application and devices.


Currently, it only supports English language only.


As a part of Free Tier Plan, you will get trial of one year. 0.0004$ is for the voice message requests and 0.00075 for text message requests.


It is a conversational chatbot APIs managed by the Facebook. In fact, This chatbot API is very helpful for the developers to integrate this API with the device or an app. is a software as a Service platform.

Thus making it very easy for the developers to make develop a chatbot using the command input by them.

Programming Language Supported and integration

It supports most of the programming language like Node.js, Python, Ruby and can be easily be also integrated with the other platforms.

Platforms Available

It can support all the application and devices that use the text messages and voice messages.


You will be surprised to know that Wit.AI nearly supports all the languages of the worlds. The languages covered by this APIs in the alphabetical order are below.

lbanian, Arabic, Azerbaijani, Bengali, Bosnian, Bulgarian, Burmese, Catalan, Chinese, Croatian, Czech, Danish, Dutch, English, Estonian, Finnish, French, Georgian, German, Greek, Hebrew, Hindi, Hungarian, Icelandic, Indonesian, Italian, Japanese, Korean, Latin, Lithuanian, Macedonian, Malay, Norwegian, Persian, Polish, Portuguese, Romanian, Russian, Serbian, Slovak, Slovenian, Spanish, Swahili, Swedish, Tagalog, Tamil, Thai, Turkish, Ukrainian, and Vietnamese.


You can request unlimited APIs calls using it. It is also for free. But it has a limitation that is not supported by any third party tools.

Microsoft Luis

This chatbot API is the service provided by the Mircosoft. It supports both the voice and text messages. It has a feature which I like very much that is Active Learning Technology. Luis uses NLP to filter the most valuable text or the information from sentences(Entities).

It has various pre-built apps like calendar, music, you can deploy it to your custom chatbot.

Programming Language Supported and integration

It supports only major SDKs of the programming languages like C# SDK, Python SDK, Node JS SDK, and the Android SDK.

Platforms Available

It supports most of the social networks for the API integration. Some of them are Facebook, Slack, Telegram, Microsoft Skype. WeChat, Email e.t.c.


English, French, Italian, German, Spanish, Korean and Chinese is some of the main language supported by the LUIS chatbot API.


It is free to use for the first 10,000  API transactions per month.  It has other plans also. $1.50 per 1,000 transactions for the text request. For the speech requests, it is set at $5.50 per 1,000 transactions.

You can also integrate the Microsoft Azure and third parties messengers using the Bot Framework.


This is one of the best solution for locally deployable chatbot. This is really comes on priority for on premise deployment. Here you need not to send the data to cloud etc. You may simply train it your end.


When you are planning to build a new conversational chatbot you make sure that you know all the basic requirements for building the chatbot. After all to know the best NLP chatbot API for your project it is necessary to find the purposes.

You may find the other NLP chatbot APIs when you search or google. But here in this article, I have listed the best NLP Chatbot APIs. Please go through the official link to learn their chatbot documentation as it will be very helpful for you.

I hope this article has given you a step to find the best chatbot APIs for your new project. You can contact us if want to add any other APIs. Please feel free to comment and contact us to ask for any chatbot related question.

At the end don’t forget to subscribe or like our Offical Facebook Page for More updates from the Chatbot World.

Join our list

Subscribe to our mailing list and get interesting stuff and updates to your email inbox.

Thank you for signup. A Confirmation Email has been sent to your Email Address.

Something went wrong.

Meet Abhishek ( Chief Editor) , a data scientist with major expertise in NLP and Text Analytics. He has worked on various projects involving text data and have been able to achieve great results. He is currently manages, where he and his team share knowledge and help others learn more about data science.
Thank you For sharing.We appreciate your support. Don't Forget to LIKE and FOLLOW our SITE to keep UPDATED with Data Science Learner