Voice calling is an essential aspect of our lives. We often make and receive calls to stay in touch with other people, make business transactions, or accomplish other conversation objectives.
Therefore, some communication companies have exposed their Application Programming Interfaces (APIs) to enable developers to create and operate powerful voice applications.
What is Voice API?
Voice API allows apps to make & receive phone calls by acting as a bridge to PSTN. Voice API gives programmers programmatic control over calls and enables them to build call logic and VoIP functionality. It allows phone-to-phone calling & app to phone calling, IVR, conference calling, and more.
With the APIs, you can make, receive, and manage calls, allowing you to build rich and reliable voice experiences. To assist you to find the best API for your specific use case, we reviewed several voice APIs based on the following four main criteria:
- API features: We looked at the various API features you can exploit to integrate voice calling capabilities into your application.
- Popularity: We assessed the popularity of the communication services. This will assist you to determine whether it’s worthwhile implementing them into your application.
- Price: We examined the cost of utilizing the APIs for powering voice calls.
- Ease of use: We reviewed the ease of using the APIs.
Ultimately, we created the following list of top 10 best voice APIs:
- Siri API
- Jeannie API
- RoboMatic.AI API
- Google Voice API
- Viber API
- Facebook Messenger API
- Twilio API
- LINE Messaging API
- Plivo API
- DiscordBot API
Table of Contents
Top 10 Best Voice APIs
TL;DR: Here’s a table summarizing our findings.
|API Features||Popularity||Price||Easy to Use|
|Siri API||Add intelligent voice assistance, provide smart answers to users, make voice queries, perform voice-related tasks||3 million users||Free and varying paid plans from $4.99 to $99.99 per month||Easy|
|Jeannie API||Add intelligent voice assistance, add user commands such as handling device settings, searching for information online, creating messages, and chatting||3 million users||Free and varying paid plans from $9.00 to $999.00 per month||Easy|
|RoboMatic.AI API||Supports voice conversations, multiple chatting sessions, group conversations, controlling devices, analyzing data||Low popularity||Free (limited usage)||Easy|
|Google Cloud Speech API||Convert audio messages to text messages||Very popular||Free (limited usage)||Easy|
|Viber API||Make and receive voice and video calls||260 million monthly users||Free||Easy|
|Facebook Messenger API||Make and receive voice and video calls||1.3 billion monthly users||Free||Easy|
|Twilio API||Make calls from mobile or web apps to landline or mobile phones, app-to-app calls, audio conferencing||1 million developers||Free (limited usage)||Easy|
|Line Messaging API||Make and receive audio and video calls||200 million monthly users||Free||Easy|
|Plivo API||Make calls, receive calls, route calls, enable voice notifications, enable voice surveys||100,000 businesses||Free (limited usage)||Easy|
|DiscordBot API||Integrate voice and text communication into gaming application||250 million users||Free||Easy|
1. Siri API
The Siri API allows you to add intelligent voice assistance to your applications, just like the Apple’s Siri.
API features: With the Siri API, you can deploy a state-of-the-art interface that provides smart answers to users having natural language questions. For example, the API can be used for making voice queries, chatting with other users, making recommendations, and performing other voice-related tasks. Furthermore, it provides other useful features such as sentence analysis and entity extraction.
Popularity: The API has been used by more than 3 million users.
Price: If you make less than 30 requests per day, you can use the API for free. Beyond the free plan, you can pay either $4.99 per month or $99.99 per month.
Ease of use: There is simple documentation to assist you to easily start using the API for building voice capabilities into your application.
2. Jeannie API
The Jeannie API is a virtual assistant that allows you to speak natural language voice commands and accomplish various tasks, just like the Apple’s Siri.
API features: The Jeannie API allows you to add voice assistant capabilities to your applications. It supports a wide variety of user commands, including handling device settings, searching for information online, creating messages, chatting, and many more. It also comes with other excellent features such as sentence analysis and entity extraction.
Popularity: The API has been used by more than 3 million users.
Price: You can use the API for free, as long as you make less than 100 requests per day. To access higher limits and more features, you can subscribe to any of the paid plans, which starts from $9.00 per month to $999.00 per month.
Ease of use: There is helpful documentation and other resources to ensure you can easily start building wonderful capabilities using the API.
RoboMatic.AI is a powerful bot that allows you to automate various tasks and make everyday business and personal communication tasks simple and fast. It can be deployed on desktop, web, mobile, or IoT applications.
API features: You can use the RoboMatic.AI API to create real-time communications between AI-built chatbots and authorized third parties. Besides supporting voice conversations, such as speech recognition and text to speech capabilities, the API also supports a wide range of various tasks, including supporting simultaneous multiple chatting sessions, supporting group conversations, controlling devices, analyzing data, and more.
Popularity: Compared to other voice APIs, the RoboMatic.AI’s popularity is still low.
Price: On the Rakuten RapidAPI platform, you can use the API for free—for limited usage. However, for extended usage, you’ll need to contact them for specific pricing.
Ease of use: There are detailed documentation and SDKs to help you in embedding voice capabilities into your application with ease.
Google has a voice API called Cloud Speech API that allows you to implement voice capabilities into your application.
API features: With the Google Cloud Speech API, you can leverage Google’s machine learning technologies to build applications that convert audio messages to text messages. For example, you can use the API to send an audio file and receive a text transcription of your message. It supports more than 120 languages from around the world and can transcribe the audio received on an application’s microphone or transcribe uploaded audio files.
Popularity: The Google Cloud Speech API service is very popular.
Price: On the Rakuten RapidAPI platform, the API is provided for free—for limited usage. However, for extended usage, you’ll need to contact them for specific pricing.
Ease of use: Google offers comprehensive and easy to follow documentation to allow developers to seamlessly integrate the API within minutes.
5. Viber API
Viber is a cross-platform communication service that provides an extensive range of calling and messaging features, including audio and video calls, expressive stickers, group chats, and many more.
API features: The Viber API allows you to tap into the application’s infrastructure and power secure conversations. With the API, you can build unique calling experiences for users around the world at scale. Furthermore, you can use the API to retrieve a user’s details and interact with other types of messages.
Popularity: As of October 2018, Viber reported more than 260 million users per month.
Price: The API is available for free.
Ease of use: Viber provides resourceful documentations and tutorials in different programming languages. Therefore, you can enable Viber voice calling in your application within just a few minutes.
Messenger is a Facebook-owned separate messaging application that makes it easy for people to communicate using instant messages, voice calls, video calls, emojis, and other exciting interactive content. It is available on the Internet and mobile operating systems.
API features: The Facebook Messenger API provides you with programmatic access to the Messenger platform so that you can build awesome communication experiences. You can use the API to integrate voice calls into your application. With the API, you can also retrieve users’ IDs, profiles, and other information, enabling you to create personalized conversations.
Popularity: Messenger trails WhatsApp as the second most used messaging application in the world. As of October 2018, it reported more than 1.3 billion users per month.
Price: The API is provided for free.
Ease of use: Facebook provides guidance on how to begin creating applications for the Messenger platform. Furthermore, there is a huge community of developers who can assist you to overcome any implementation challenges.
7. Twilio API
Twilio is a popular developer platform that allows you to integrate voice, video, text messaging, and other communication abilities into your mobile and web applications.
API features: The Twilio API offers access to carrier networks and communications facilities from around the world, allowing you to craft intelligent and reliable voice applications. With the API, you can design applications capable of making, receiving, and monitoring phone calls, making calls from mobile or web apps to landline or mobile phones, performing app-to-app calls, and carrying out audio conferencing.
Popularity: Twilio is popular across the world. It is used by more than one million developers around the world.
Price: You can test the Twilio API for free. For extended usage, you’ll need to contact them for specific pricing.
Ease of use: Twilio has comprehensive documentations and SDKs for creating crystal clear voice calling capabilities using a programming language of your choice.
LINE is an application that supports communications on a wide range of electronic devices using video and voice calls, pictures, and text messages.
API features: LINE offers a Messaging API that empowers developers to create reliable two-way communication capabilities between their applications and LINE users. You can use the API to send and receive various types of messages, including audio messages and video messages.
Popularity: Even though LINE is mostly popular in some Asian countries such as Japan, Taiwan, and Indonesia, it has also gained popularity across the world. As of October 2018, it recorded more than 200 million active users per month, globally.
Price: The API is provided for free.
Ease of use: The LINE Messaging API is easy to use. The company offers comprehensive documentation to assist developers in making the most of the API without many programming obstacles.
9. Plivo API
Plivo is a service that enables developers to embed voice calling and text messaging into their mobile and web applications without the limitations of carrier lock-ins.
API features: The Plivo API allows you to manage voice calls. You can use it to make calls, receive calls, route calls, and carry out other call management tasks and sidestep the complexities of telecom carriers. With the API, you can enable conference calls, voice notifications, voicemails, voice surveys, and call forwarding in more than 200 countries.
Popularity: The API is currently used by more than 100,000 businesses around the world.
Price: You can test the Plivo API for free. For extended usage, you’ll need to contact them for specific pricing.
Ease of use: Plivo offers pre-built templates and exhaustive documentation to help you in hitting the ground fast and without many programming hassles.
10. DiscordBot API
Discord is a freeware VoIP application and digital distribution software that is mainly popular among the gaming community. It’s widely used to create games with voice, text, image, and video chatting capabilities. The software can be deployed on a wide range of platforms, including Windows, iOS, Linux, and web browsers.
API features: With the DiscordBot API, you can integrate voice and text communication into your gaming application. It is greatly customizable and comes with quality sound to power engaging chats between users.
Popularity: As of July 2019, the software had more than 250 million unique users.
Price: The DiscordBot API is available for free.
Ease of use: There is detailed and easy to follow documentation to help you in integrating the API within minutes. There is also an active community of developers who can assist you with any implementation challenges.
That’s Rakuten RapidAPI’s list of Top 10 Best Voice APIs. You may also like to check our list of best chatbot APIs and SMS APIs. We hope you’ll find an API that you can incorporate into your application and enable powerful voice calling capabilities!
About Rakuten RapidAPI
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