V 1.0 is available

The Mizu universal WebPhone is a SIP standards based VoIP client software embeddable in any wfulebpage as a Browser Softphone, or used as a VoIP JavaScript library to build your custom web based VoIP solution, be it a simple click to call button or complex solution integrated with your existing business logic. Based on the industry standard SIP protocol, it is compatible with all VoIP devices and services. It can call any other SIP phone (softphone or ip phone for free charge) or any landline and mobile number via a VoIP service provider of your choice including your own VoIP server if you have one. All usual call features are implemented (call forward, call transfer, conference, etc).

The webphone is a self-hosted web VoIP client solution, shipped with life-time license, without any external service dependencies, totally owned by you.

Unlike other solutions, the mizu webphone is a truly cross platform effective solution to the "VoIP from browser" problem, using multiple different SIP/media engines targeting different platforms with the optimal solution to take out the most from the client side possibilities usable from the browsers:

  • Java VoIP engine: for all java enabled browsers providing native SIP/RTP
  • WebRTC SIP: for modern browsers with HTML5/WebRTC support
  • NS engine: native service/browser plugin (once click install to achieve the best VoIP performance)
  • Flash VoIP: for compatibility with some old browsers
  • App: for platforms when VoIP plugins are otherwise impossible (iOS/Safari)
  • P2P and Callback: if your VoIP server has an API for these and no better alternatives found
  • Native dial: might be used on mobiles when VoIP is not possible (for example no network access)
The "best" suitable engine is automatically selected based on browsers/OS capabilities and server support (You can also set or prioritize the engines to be used by the configuration).
The default user interfaces are implemented as HTML/CSS which can be customized after your needs. Developers can use the API to implement any custom functionality or a custom design (any technology with JavaScript binding including HTML, CSS, Flash or generated from server side by PHP, .NET, J2EE, Node.js or others).

The download package includes the followings:
  • the software itself to be copied to your website
  • documentation
  • JavaScript library: an easy to use JavaScript API to implement your custom VoIP solution
  • a web softphone implementation: you can easily rebrand and customize it, then deploy to your website
  • a click to call button: a simple click to call solution
  • usage examples and templates
The public version has some limitations and a final package is sent to you on your order (you can use the public version for all tests, development and integration and then just replace it with your final build once you are ready)

Download webphone package

We would appreciate any feedback you can provide regarding the webphone, including issues you have encountered, suggestions and feature requests.

how it works?

browser sip engines


What is a webphone?

A webphone is a software program for making telephone calls over the Internet (VoIP/SIP) using a web browser, rather than native applications or a dedicated hardware phone.


  • Runs in any browser and all OS with webrtc, java, flash or native plugin support (Firefox, Chrome, IE 6+, Edge, Opera and others on Windows/Linux/MAC/iOS/Android and others)
  • Standard SIP client for voice calls (in/out), chat, conference and others
  • SIP and RTP stack compatible with any standard VoIP servers and devices like Cisco, Voipswitch, Asterix, softphones, ATA and others
  • Transport protocols: UDP/TCP/TLS/DTLS/SRTP/tunnel/websocket/RTMFP/RTSP
  • Seamless protocol conversions if necessary: RTMP to SIP, WebRTC-SIP gateway for browser-SIP (protocol conversion avoided whenever possible)
  • NAT/Firewall/Proxy traversal: stable SIP and RTP ports ,keep-alive, rport support, ICE, fast STUN, SOCKS proxy traversal, HTTP proxy traversal and auto configuration
  • Codec: G.711 (PCMU, PCMA), G.729, GSM, iLBC, SPEEX, OPUS (wide-band HD audio)
  • Audio enhancements: PLC (packet loss concealment), AEC (acoustic echo canceller), Noise suppression, Silence suppression, AGC (automatic gain control), high-quality low-latency audio and auto QoS
  • Call divert features: redial, mute, forward, hold, transfer (attended and unattended), conference
  • IM/Chat, DTMF, voicemail MWI
  • NS + Java features such as voice recording and call barge-in
  • Balance/rating display, call timer, CallerID display
  • No server side dependencies. You can use the webphone to add VoIP to any kind of webpage, be it a simple static page or a java script oriented website. In case if you are using a server side stack, the webphone can be integrated with any technology including PHP, .NET, java servlet, J2EE , Node.js and others. Use any OS and any web server (IIS, Apache, nginx, NodeJS, java, others)
  • JavaScript API: web developers can build any custom VoIP functionality using the webphone as a JS library
  • Integration: the webphone provides an easy way to integrate it with your server (user sign-up, sms, balance, callback, recharge and others website/app-store/VoIP/API usage)
  • Branding and customization: Use with your own brand. Customizable, feature rich responsive user interface with ready to use, modifiable skins
  • Flexibility: all parameters/behavior can be changed/controlled by URL parameters, preconfigured parameters and/or from java script

Compatible with all VoIP/SIP device and software:

  • PBX (Asterisk, Trixbox, Avaya, 3CX, Broadsoft, Alcatel, NEC, others)
  • VoIP servers (Mizu, Voipswitch, Cisco, Huawei, others)
  • SIP proxy (SER, OpenSIPS, others)
  • SIP softphones (X-Lite, Bria, Jitsi others)
  • devices (gateways, ATA’s, IP Phones, others)
  • VoIP service providers (Vonage, others)
  • any SIP capable endpoint (UAC, UAS, proxy, others)


Windows / Linux / MAC / iOS / Android

Usage examples

Flexibility was one of our top priorities. The webphone package can be used in many ways:

  • JavaScript VoIP library for developers
  • As a ready to use softphone running from your website, so the user will not have to install a separate standalone softphone software (just set your VoIP server address to go)
  • Custom softphone (you can customize the softphone including sip settings, design and branding)
  • VoIP service providers can deploy the mizu webphone on their web pages allowing customers to initiate SIP calls without the need of any other equipment directly from their web browsers
  • Add VoIP capabilities for any software
  • As ready to use VoIP click to call solution (just preconfigure with a sip account and a number to call)
  • Buy/sell portals
  • Callcenters (easy to integrate with existing call center software suite or CRM frontpage)
  • Browser VoIP SDK to build your product
  • SIP browser plugin
  • Click to call from email signature
  • jQuery phone plugin
  • SaaS services
  • Embedded VoIP client in various devices (PBX box, IP phone and others)
  • VoIP CRM integration
  • VoIP plugin for PHP, .NET, JSP, Node JS or any popular server script language
  • Social networking websites
  • As a portable communication tool between company employees
  • VoIP enabled sales and support pages where people can call your agent from your website.
  • VoIP enabled blogs and forums where members can call each other
  • As a facebook phone
  • Wordpress voip plugin
  • HTML Call me button
  • VoIP call from Email signature
  • Help desk VoIP call from browser
  • Browser phone plugin
  • OEMs to bundle VoIP into any distributed software package
  • For voip service providers to offer click to call functionality for their customers
  • Callback and phone to phone calls handled by VoIP server
  • SIP phone plugin for all popular CRM and blog web engine
  • The rest is up to your imagination...

The webphone is recommended for:

  • voip service providers (fully customizable/branded solution optimized for your SIP server)
  • non-technical people with a need to add VoIP to website (copy-paste html code, just set your SIP provider address in the configuration to begin the usage)
  • web developers (build any web VoIP solution using the JavaScript API)
  • web designers (easily add VoIP call capabilities to any website, modify existing skins or create your own with simple HTML/CSS)
  • call centers
  • individuals, small-businesses and enterprise corporations

Check the online demo


webphone screenshots

WHY should i use?

Solves the ” VoIP from browser” problem
The Mizu Webphone provides a reliable solution for today's fragmented browser market with sub-optimal VoIP capabilities by implementing VoIP engines with multiple technologies and automatically selecting the "best" engine available on client user OS/browser.
This is especially important on websites/projects where VoIP is a key functionality,  such as call-centers and VoIP service providers offering call capabilities for their customers directly from browsers with no or minimal quality compromises, connecting directly  from user browser to the SIP server without the use of intermediary gateways or protocol convertors.
The webphone is optimized for native SIP/RTP in most circumstances, regardless of user OS and browser.
To sum up, the webphone is focusing on the following goals:
-maximize quality: use the best possible native SIP/RTP VoIP engine directly from client browsers whenever possible
-maximize coverage: true cross-platform capabilities to cover all OS/browser combination, so the users will be able to make VoIP calls regardless of the circumstances (any OS, any browser)

The webphone fulfils the needs of both developers and non-technical users.
You can use the built-in ready to use softphone or click to call solutions, or leverage your custom solution using the numerous configuration options or the webphone java script API, if you are a web developer with JS knowledge.
The mizu webphone provides an easy and reliable way to offer VoIP to your customers,  integrated in your website or application.

Cross platform browser VoIP client
The webphone is platform independent so you can use one single app to cover all platforms.
You can forget about the complexity in the background as the webphone will just magically run on all platforms, offering the "best" suitable engine for the endusers.
All this is covered by a simple JavaScript API allowing web developers to create custom VoIP solutions from any Java Script framework or with pure JS.
A single solution supporting all platforms where VoIP in browser is possible including Windows, Linux, MAC OSX, Android, iOS, Solaris, Chrome OS and others.

Native-like VoIP quality and reliability from browsers
With its built-in multiple different SIP/media engines it is able to take out the most from the browsers’ VoIP capabilities using native SIP/RTP whenever possible with a smooth failover to browser technologies such as WebRTC and Flash when needed.
By using the Mizu webphone you will finally be able to offer browser based VoIP services with the same quality as native desktop (softphone) and hardware (IP phone) based solutions.

Ease of use
Copy-paste html code in your website, no developer knowledge is required, with all settings optimized by default. You only have to set your VoIP server address to begin.
Can be integrated into any environment, be it a simple static page, a JavaScript application (pure or any framework), any server side technology (PHP, .NET, JEE, NodeJS, etc) and using any webserver (Apache, IIS, nginx and others).
Let your clients easily initiate new voice calls directly from your website without the need to download any software. The web phone will be hosted by your webserver (one single file)
Calls can be initiated from scripts, from user input by typing a phone number, by selecting from contact list, by a click to call button or by your custom application logic using the JavaScript API or generated from server side scripts.
It takes only a few minutes to have a functional VoIP client deployed on your website connecting to your SIP server or your VoIP provider account.

Full customization, skinning and branding is supported by numerous settings or using the java script API if you have web development skills. The numerous configuration options will help to closely integrate with your existing infrastructure and to make the most of the offered features.
You can also completely change/remove/create your own user interface using your favorite tool, be it a static page or dynamically generated HTML/HMTL5, CSS/CSS5, AJAX, FLASH, etc.

Based on telecom standards
Connects to any standard based sip server (like Cisco, Asterisk, etc).
Integrated SIP and RTP stack with industry standards codecs including G.729 and wideband HD audio. The webphone can connect directly to your VoIP server or third party IP phones and softphones just like any other standard VoIP client does. The webphone was designed both for SMB or corporations with large call traffic requirements.

Life-time license
Avoid dependency from subscriber based web phone services. Use this webphone component to be able to make calls via your preferred VoIP service provider or via your own VoIP server. Pay once to get a life-time license with no any recurring payment or hidden charges. The Advanced and Gold versions ships without any limitations so the usage is unlimited.

Advantages over pure WebRTC solutions
WebRTC is supported by a part of modern browsers, however it has clear disadvantages when using with SIP networks such as weak codec support (no G.729), browser differences and incompatibilities with its black-box media stack, unneeded extra layer and error phone complexity to convert from websocket/DTLS to clear SIP/RTP with extra server side processing requirements and it is still not supported by all browsers.
To bypass all these weaknesses the Mizu Webphone has built-in native VoIP engines to be used whenever possible.
This doesn't meant that the webphone ignores WebRTC. Actually, it provides an optimized WebRTC stack with seamless integration with your SIP network, automatically used when more native engines are unavailable/disabled in users browser.
The webphone is also usable when WebRTC is not available (not supported by client browser, not supported by server side or disabled by settings).
In the future we plan to add even more WebRTC related features, with a focus to bring WebRTC as close as possible to native SIP/RTP.

Advantages over browser plugins, flash and other similar solutions
Modern browsers are fragmented enough to make it impossible to cover them with one of these solutions and to be able to provide quality services for endusers at the same time.
Browser plugins have to be build/maintained and deployed separately for all browsers and the endusers need to take extra steps to activate them. They have inferior VoIP capabilities due to recent restrictions introduced by browser vendors which is just getting worse and worse over time.
Flash has its own well known issues (only basic code support, requiring an RTMP SIP server side gateway which adds extra complexity and expensive media conversion) and it has also started to be banned in recent browser releases.

New approach
By bringing browser VoIP as close as possible to the traditional SIP standards, service providers will be able to unlock new possibilities leveraging browser based VoIP call capabilities with voice quality similar to desktop softphones and hardware IP phones, consistently across all platforms and all browsers.
The multi-engine / unified API is a new unique solution on the VoIP market, offering great opportunities for established and new VoIP service providers and for anyone who wishes to offer VoIP call capabilities from their website with the maximum call quality and coverage possible,  for all mainstream platforms including mobile and desktop browsers.
The Mizu webphone is a flexible future proof solution by allowing to easily add/change/re-prioritize the underlying VoIP engines as browsers will change over time.