Best Free Voice Calling API & SDK Providers of 2025

Bird, previously known as MessageBird, represents the future of CRM tailored for Marketing, Sales, and Payments, facilitating more than 5 trillion messages each year across platforms like Email, SMS, and WhatsApp. Top brands efficiently enhance their growth through Bird by engaging in tailored interactions across these channels. Innovative organizations around the globe utilize Bird's robust applications and APIs to create effective communication solutions. Start your journey today and connect with your customers seamlessly across various channels, catering to diverse use cases regardless of location. You can send marketing messages, push notifications, order confirmations, delivery updates, and much more. If operational challenges are hindering your growth, leverage automated conversations and workflows to gather essential information upfront, minimize manual tasks, establish self-service options, and direct chats to the appropriate agents. With our dependable, auto-scaling APIs, you can quickly get started with extensive documentation, comprehensive API references, and user-friendly SDKs at your disposal. Experience the power of streamlined communication and watch your business thrive.

Welcome to TENIOS, the cloud communications provider of the Apifonica Group. TENIOS is German-based and specializes in cutting-edge AI voicebots and telephony solutions for businesses. Their mission in short words: Bringing Conversational AI to the world. Their passion for automation unites a team of experts in Cloud Technology, Telephony, and AI to help businesses automate communication and related business workflows. TENIOS Voicebots handle outbound and inbound calls, call back leads, pre-qualifiy them, instantly update CRM data, and create reports to scale customer communications. The comprehensive telecom-platform offers services such as virtual phone numbers, intelligent call routing, interactive voice response (IVR) systems, SMS, RCS, and a robust Voice API for seamless integration of voice applications. With over two decades of experience and hosting in Germany, TENIOS ensures reliable and scalable communication solutions tailored to meet diverse business needs.

Authkey.io stands as an exceptional Enterprise Omni Channel API platform, offering an extensive suite of communication tools and APIs meticulously designed to empower businesses in their quest for efficient and secure customer engagement. SMS API:A seamless communication symphony with its event-based messaging prowess. This facet encompasses the seamless orchestration of Bulk SMS delivery, transactional messages, one-time passwords (OTP), and the authentication process through call-based interfaces. Voice API: This dynamic capability ensures the delivery of OTPs through vocal messages, providing an alternative avenue that ensures the recipient's prompt access. Email API: Reliable and rapid delivery of emails, serving critical functions such as password verification, account creation, OTP distribution, and email validation. WhatsApp Business API: The contemporary business landscape requires a direct conduit to reach the massive audience on the WhatsApp API facilitate this engagement, enabling businesses to establish a direct line of communication with their audience. Two-Factor Authentication (2FA) API: Seamlessly dispatching OTPs, verifying logins, and bolstering the security architecture of business software, CRM systems.

Dyte's Video SDK and APIs are SOC 2, GDPR, and HIPAA compliant. Embed scalable, customisable and secure video call into your web or mobile app with just few lines of code. It is compatible with Android, iOS, React Native, Angular and many more languages. With an uptime of 99.99%, industry-leading documentation, UI kit and out of the box plugins, customize the video experience within minutes.

Streamline the development of your video calling application by saving valuable time on UI and feature implementation. By using only five lines of code, you can seamlessly integrate video calling into your project. Simply generate an API Key to create a secure connection between your application and Video SDK. This setup ensures a robust end-to-end encrypted link between your app and our servers. By incorporating straightforward JavaScript code into your website, you'll find it easy to build an interactive video calling solution. With just a few lines of code, you can create an engaging video calling app tailored to your needs. Additionally, the Analytics Dashboard provides insights to track service usage and allows for manual operational control. Everything you need is included to create custom and branded live shopping experiences tailored for eCommerce brands of any size. Furthermore, all the necessary tools are available to develop secure telemedicine communication APIs and SDKs, ensuring safety and compliance at any scale. This comprehensive approach empowers you to innovate and expand your digital offerings efficiently.

Enhance your applications by integrating captivating real-time voice, video, and in-app chat functionalities through ZEGOCLOUD's communication APIs. With just four lines of code, you can kickstart the process and unlock a wealth of interactive features. Utilize our comprehensive voice, video, and in-app chat SDKs to tailor the communication capabilities your users desire, allowing them to connect, share, and engage with one another at any time and from anywhere. Elevate the user experience with a diverse range of add-ons such as emotionally intelligent avatars, AI-enhanced video effects, interactive whiteboards, and much more. Ensure seamless communication quality in real-time while also gaining valuable insights into user interactions through our advanced monitoring and analytics tools, empowering you to swiftly address any challenges and perpetually enhance your offerings. ZEGOCLOUD's innovative social solutions enable you to create personalized one-on-one and group video calls, lively audio rooms, and dynamic social live streaming, fostering connections and enjoyable experiences for your users. By leveraging these tools, you can cultivate a vibrant community where users can forge lasting relationships and share memorable moments together.

With over 700 direct carrier connections and 60+ offices on 6 continents, Infobip is a global leader in omnichannel communication. We make it our business to simplify how brands connect with, engage and delight their customers at global scale. Our programmable communications platform delivers a suite of tools for advanced customer engagement and support, plus security and authentication. We make this available to you across the widest range of communication channels possible. THE INFOBIP ADVANTAGE (1) Personalized omnichannel customer connections Achieve deeper customer engagement across the widest selection of local and global channels, including: SMS, RCS, WhatsApp, voice, video, email and the most popular chat apps. (2) Global reach, local presence Our 60+ offices around the world allow us to react faster. We provide 24/7 customer support, technical solutions in-line with needs and local requirements — based on proven best practices. (3) Full stack customer engagement Deliver better outcomes for your business by enhancing your communications with fully integrated contact center, marketing automation, and chatbot building solutions informed by our customer data platform.

Mesibo serves as a robust real-time communication platform that enables the seamless integration of messaging, group chats, voice calls, and video conferencing into both mobile and web applications. When developing the Mesibo APIs, our primary focus was on ensuring reliability, performance, and scalability, as we recognized that overly complex APIs can lead to unnecessary complications and increased error rates in applications. Rather than following the trend of convoluted API designs, we have prioritized simplicity while maintaining powerful capabilities. In this section, we will delve into the intricacies of Mesibo's real-time APIs. It is advisable to check out the source code of one of the sample applications available on GitHub to gain insights into how these APIs are effectively utilized. This approach will facilitate your ability to write cross-platform code seamlessly. In the subsequent sections, we will outline the APIs along with their respective names and parameters, providing you with a comprehensive understanding of their functionality. Additionally, this will empower you to implement the APIs more effectively in your projects.

Create your own messaging platform complete with chat and video call capabilities in just a few minutes by utilizing the QuickBlox chat API and SDK. QuickBlox offers an instant messaging API that seamlessly integrates chat and calling features into any application, whether it be for Android, iOS, or the web. It encompasses all the essential functionalities needed to develop a top-notch messaging app, including high-quality one-on-one and group calls powered by WebRTC. Additionally, it provides flexible data and file storage solutions that enhance your messaging experience. You can easily integrate ongoing business workflows with real-time alerts and notifications, as well as share and link a wide array of file types, including images, audio, video, documents, and more. QuickBlox is currently utilized by over 30,000 software developers and organizations around the globe. As a HIPAA-compliant chat solution, QuickBlox is trusted by healthcare providers worldwide, catering to a diverse clientele that ranges from large corporations managing millions of healthcare and insurance records to innovative startups relying on our services for their telemedicine communication needs. This versatility highlights the effectiveness of QuickBlox in meeting various industry demands.