Best Free Voice Calling API & SDK Providers of 2025

Compare the Top Free Voice Calling API & SDK Providers as of September 2025

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What are Free Voice Calling API & SDK Providers?

Voice calling API and SDK providers offer developers with the necessary tools to integrate voice calling functionality into their applications. These providers typically offer a range of options, including APIs that allow for an easy integration process, as well as SDKs that provide more advanced features such as call recording and real-time transcription. They also often provide comprehensive documentation and technical support to assist developers in implementing these services. Some of the major players in this field include Twilio, Voximplant, and Nexmo, each offering their own unique set of features and pricing plans. In general, these providers aim to make it easier for businesses to incorporate voice calling capabilities into their products without having to build them from scratch. Compare and read user reviews of the best Free Voice Calling API & SDK providers currently available using the table below. This list is updated regularly.

1

Bird

Bird

Bird (formerly MessageBird) is the next-generation CRM for Marketing, Sales, and Payments, powering over 5 trillion annual messages across Email, SMS, and WhatsApp. Leading brands grow cost-efficiently with Bird through personalized interactions on Email, SMS, and WhatsApp. The world's most innovative companies build communication solutions using Bird's applications and APIs. Get started today and talk to your customers over any channel, for any use case, anywhere in the world. Marketing messages, push notifications, order updates, delivery alerts and more. Operational bottlenecks slowing your growth? Use automated conversations and workflows to collect critical information up front, reduce manual tasks, implement self-service flows, and route chats to the right agent. Get up and running in minutes on our reliable, auto-scaling APIs with extensive documentations, complete API references and intuitive SDKs.

1 Rating

Starting Price: $45 per month

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2

TENIOS

TENIOS

TENIOS is a German-based communications provider specializing in advanced AI phone assistant and telephony solutions for businesses. Their 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. TENIOS also provides AI-powered phone assistants to automate customer interactions, enhancing efficiency in contact centers and diverse sectors with high call volumes. With over two decades of experience and hosting in Germany, TENIOS ensures reliable and scalable communication solutions tailored to meet diverse business needs.

1 Rating

Starting Price: €50/ month (Pay as YouGo)

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3

Authkey

Authkey.io

Authkey is a multi-channel CPaaS platform providing SMS API, WhatsApp Business API, Voice API, Email API, and Google RCS. It helps businesses send notifications, promotional messages, transactional messages, OTPs, 2FA, and more. Designed for responsiveness and ease of use, Authkey allows you to start without adding any credit cards. Authkey offers a free sandbox account for building, testing, and deploying. It supports easy-to-integrate APIs for all channels and over 1,000 automation options via Zapier, Pabbly, Integrately, and other partners. You can easily push bulk campaigns through all channels. WhatsApp Chatbot for intelligent customer query responses. Join over 200 active businesses working with us and grow together.

Starting Price: $0

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4

Dyte

Dyte

Dyte's Video SDK and APIs are SOC 2, GDPR and HIPAA complaint. That lets you embed scalable, customisable and interactive video calls within minutes into your Web, Desktop or mobile apps. Collaborate efficiently with HD video, chat, screen sharing, whiteboard, emoji reactions, file sharing and everything a user packaged within one SDK. Dyte's Video Conferencing SDK & APIs are comfortable with React JS, Angular, JavascriptMobile: Flutter, Kotlin, Swift, React Native, Android, iOSDesktop, Electron. With an uptime of 99.99%, industry-leading documentation and out of the box plugins, customize the video experience for your ed-tech, tele-health, fitness, HR-tech, social or gaming platform. Use Dyte's SDKs to build fully custom video experiences powered by a robust infrastructure. With our out-of-the-box chat, plug-ins, recording, and several useful features, Dyte is an all-in-one SDK to help you take video collaboration to the next level. Dyte offers 10K free credits each month

Starting Price: $0

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5

Video SDK

videosdk.live

Saving your time in building UI and features for your video calling application. With just 5 lines of code, you'll be able to integrate video calls into your application. Generate API Key to eastablish connection in-between your app to Video SDK. It enables end-to-end secure connection in-between your app and our servers. Install the simple JavaScript code in your website. In just few lines of code, you can build interactive video calling app. Analytics Dashboard will help you to monitor all the usage of services and also provide manual operations control. Everthing you need to build custom and branded live shopping experiences for eCommerce brands at any scale. Everthing you need to build custom and branded highly secure telemedicine communication APIs and SDKs at any scale.

Starting Price: $0.6 per min

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6

ZEGOCLOUD

ZEGOCLOUD

Embed engaging real-time voice, video, and in-app chat experiences into your apps with ZEGOCLOUD's communications APIs. Get started with 4 lines of code and enable enriched interactions with more features. Use our voice, video, and in-app chat SDKs to develop the exact communication features your users need to connect, share, and interact with each other anytime, anywhere. Liven up the interactions and elevate the vibes for your users with a rich set of add-ons, including emotionally responsive avatars, AI-powered video effects, whiteboards, and more. Monitor the quality of communications in real-time and gain insights into your user experience with our powerful monitoring and analytics tools, so you can respond to any issues swiftly and improve your services continuously. ZEGOCLOUD's social solutions help you build 1-on-1 and group video calls, live audio rooms, and social live streaming into your apps to help your users connect and have fun together.

Starting Price: $0.59 per 1000 minutes

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7

Infobip

Infobip

Infobip is a global leader in omnichannel engagement powering a broad range of messaging channels, tools and solutions for advanced customer engagement, authentication and security. With over 700 direct carrier connections and 60+ offices on 6 continents, Infobip is the #1 choice of some of the world's biggest companies to scale their customer communications. We help our clients and partners overcome the complexity of consumer communications, grow their business and enhance customer experience, all in a fast, secure and reliable way. With Infobip, you can achieve deeper customer engagement across the widest selection of local and global channels, including: SMS MMS RCS Live Chat WhatsApp Business Apple Messages for Business Facebook Messenger Instagram Business Telegram Viber Voice / VOIP Video Email

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8

mesibo

mesibo

mesibo is a powerful real-time communication platform to quickly add robust real-time messaging, group chat, voice, and video calls, conferencing into your mobile and web applications. The key objectives while designing mesibo APIs were reliability, performance, and scalability. We have seen APIs as complex as the universe making apps unnecessarily complex and error-prone. We have instead worked hard to make mesibo APIs simple, yet powerful. In this section, we will explore mesibo real-time APIs in detail. It is highly recommended that you also refer to the source code of one of the mesibo sample app in GitHub to learn how APIs are used. This makes it easy for you to write cross-platform code across platform. In the following sections, we will describe APIs with name and parameters.

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9

QuickBlox

QuickBlox

Build your own messenger with chat and video calling in minutes using QuickBlox chat API and SDK. QuickBlox provides instant messaging API that allow chat and calling functionality to be added to any Android, iOS, or Web application. All features that you need to build a great messaging application. High quality one‑to‑one and group calling built on WebRTC. Flexible data and file storage that compliments your messaging. Integrate your current business processes with real‑time alerts and notifications. Share and link all types of files (images, audio, video, docs, and other file formats). Over 30,000 software developers and organizations worldwide are using QuickBlox messaging API. QuickBlox is a HIPAA‑compliant chat solution trusted by Healthcare businesses worldwide. We serve a variety of customers ranging from large corporations storing millions of healthcare and insurance records to startups entrusting their telemedicine communication to us.

Starting Price: $99 per month

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