Top Voice & Conversational Interfaces companies

Parloa builds no-code conversational AI agents for European enterprise contact centers, specializing in voice and omnichannel automation.

Enterprise Voice Agents · Series D $350M

Enterprise Voice Agents

Series D

$350M

HQ

Dialpad provides a cloud business communications platform with built-in voice AI for real-time transcription, sentiment analysis, and agent coaching.

Contact Center AI · Series F $170M

Contact Center AI

Series F

$170M

HQ

Sesame builds fast, high-fidelity voice models for conversational AI with a focus on multilingual support and low-latency inference.

TTS / Voice Synthesis · Series B $250M

TTS / Voice Synthesis

Series B

$250M

HQ

Cresta provides real-time AI coaching and automation for contact-center agents, analyzing voice and chat to improve sales and support outcomes.

Contact Center AI · Series D $125M

Contact Center AI

Series D

$125M

HQ

Kore.ai provides an enterprise conversational AI platform for contact centers, covering voice, chat, and automation across 100+ channels.

Enterprise Voice Agents · Growth $150M

Enterprise Voice Agents

Growth

$150M

HQ

Deepgram provides deep-learning-based automatic speech recognition and text-to-speech APIs for real-time transcription and voice synthesis.

STT / ASR · Series C $130M

STT / ASR

Series C

$130M

HQ

Observe.AI provides voice analytics and agent-assist tools for contact centers, analyzing 100% of calls for compliance and coaching.

Contact Center AI · Series C $125M

Contact Center AI

Series C

$125M

HQ

PolyAI builds conversational AI for enterprise contact centers, specializing in restaurant reservations, hospitality, and logistics support.

Enterprise Voice Agents · Series D $86M

Enterprise Voice Agents

Series D

$86M

HQ

Cartesia develops ultra-low-latency voice models including Sonic, achieving ~40ms time-to-first-audio for real-time conversational AI.

TTS / Voice Synthesis · Series B $100M

TTS / Voice Synthesis

Series B

$100M

HQ

SoundHound AI builds a voice-native conversational AI platform powering in-car assistants, restaurant drive-thru and phone ordering, and enterprise agents through its Amelia platform.

Enterprise Voice Agents · SPAC merger (IPO)

Enterprise Voice Agents

SPAC merger (IPO)

—

HQ

LiveKit provides open-source infrastructure for real-time audio and video, powering voice-agent orchestration and WebRTC-based communication.

Voice Agent Infrastructure · Series C $100M

Voice Agent Infrastructure

Series C

$100M

HQ

Cognigy builds enterprise conversational AI for customer service, supporting voice, chat, and omnichannel deployments.

Enterprise Voice Agents · Acquired NICE

Enterprise Voice Agents

Acquired

NICE

HQ

AssemblyAI provides AI-powered speech-to-text APIs with sentiment analysis, speaker diarization, and real-time transcription features.

STT / ASR · Series C $50M

STT / ASR

Series C

$50M

HQ

Sanas builds real-time accent conversion technology for contact-center agents, translating non-native accents to standard dialects on live calls.

Accent Conversion · Series B $65M

Accent Conversion

Series B

$65M

HQ

Yellow.ai provides a conversational AI platform for customer service and employee support with voice, chat, and automation features.

Enterprise Voice Agents · Series C $78.2M

Enterprise Voice Agents

Series C

$78.2M

HQ

Wispr Flow makes an AI voice-dictation app that turns natural speech into clear, formatted text in any application across Mac, Windows, iPhone, and Android.

Voice Dictation · Series A $25M

Voice Dictation

Series A

$25M

HQ

Vapi provides a developer platform for building and deploying voice AI agents with sub-second latency and flexible integrations.

Voice Agent Infrastructure · Series B $50M

Voice Agent Infrastructure

Series B

$50M

HQ

Speechmatics offers automatic speech recognition in 50+ languages with real-time transcription and on-premises deployment options.

STT / ASR · Series B $62M

STT / ASR

Series B

$62M

HQ

Rasa builds open-source and enterprise conversational AI for on-premise voice and text assistants, popular in regulated industries.

Enterprise Voice Agents · Series C $30M

Enterprise Voice Agents

Series C

$30M

HQ

Hume AI builds empathic voice models that detect and generate emotional prosody in speech for more human-like conversational agents.

Emotion & Prosody Models · Series B $50M

Emotion & Prosody Models

Series B

$50M

HQ

Bland AI offers a platform for deploying outbound and inbound phone-based conversational agents at scale.

Voice Agent Infrastructure · Series B $40M

Voice Agent Infrastructure

Series B

$40M

HQ