Voice features

Build, scale, and operate voice applications.

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Route calls and handle media

  • Essential voice features
  • Advanced call control

    Use real-time RESTful APIs to receive, initiate, and control calls.

  • Twilio Conference

    Create audio conferences with up to 250 participants, mixed locally to minimize latency.

  • TaskRouter

    Route incoming phone calls to the people that can best handle them.

  • Speech Recognition

    Convert speech to text and analyze its intent during any voice call.

  • Text-to-speech

    Speak text to callers in 26 languages and accents.

  • The Twilio difference
  • Queue

    Build call queues with intelligent hold and whisper experiences.

  • Call Recording

    Record, store, and transcribe calls with just one line of code.

  • Answering Machine Detection

    Determine if an outbound call made has reached a live person, answering machine, or fax.

  • Audio playback

    Play prerecorded voice prompts and music.

Use any number and device

  • Essential Voice features
  • Local Phone Numbers

    Instantly acquire local, national, mobile, and toll-free phone numbers in more than 100 countries with a single API.

  • Toll-Free Phone Numbers

    Use your existing toll-free number or a new Twilio number in the U.S., Canada, and U.K.

  • The Twilio Difference
  • Clean Phone Numbers

    Twilio Phone Numbers are validated to work as advertised and free of unwanted calls.

  • Call within browsers and apps

    Enable phone calling from within any web interface or mobile app using Twilio SDKs.

  • SIP Interface

    Route calls from your existing VoIP infrastructure to Twilio for programmatic call control without migrating hardware or carriers.

Build and debug faster

  • Essential Voice features
  • Documentation

    Start building and get unstuck quickly with how-to guides, sample code, and extensive API documentation.

  • Helper libraries

    Program in the language you already use with any one of our 32 helper libraries.

  • Access roles

    Manage user permissions with policy-based access roles for admin, developer, and billing.

  • The Twilio difference
  • Voice Insights

    Use network and device performance data during WebRTC calls to programmatically improve call quality.

  • Lookup

    Verify the format, carrier data, and caller information for every phone number with the Lookup API.

  • Monitor

    Troubleshoot issues faster with logs, alerts, and threshold-based triggers.

The Twilio advantage
  • Communicate reliably

    Experience a 99.95% uptime SLA made possible with automated failover and zero maintenance windows.

  • Operate at scale

    Extend the same app you write once to new markets with configurable features for localization and compliance.

  • Many channels

    Use the same platform you know for voice, SMS, video, chat, two-factor authentication, and more.

  • No shenanigans

    Get to market faster with pay-as-you-go pricing, free support, and the freedom to scale up or down without contracts.