Alternatives to Synthio Labs

AI agents that answer patient calls, book visits, and recover no-shows across voice, SMS, email, and web.

Inworld is a realtime voice AI platform for developers building full-duplex voice agents with TTS, STT, and zero-markup LLM routing.

PolyAI builds enterprise voice AI agents that handle complex customer calls in 40+ languages

Build real-time conversational AI voice and chat agents that listen, understand, and act in 70+ languages.

Enterprise voice AI agents running on Synthflow's own telephony network, from $30,000/year

Enterprise Voice AI platform with in-house telephony and the BELL deployment framework for automating phone calls at scale.

Decagon is an enterprise AI concierge platform for omnichannel customer support across chat, voice, and email.

Agentic AI for property management and healthcare that answers every lead, resident, and patient 24/7.

Omnichannel generative AI platform for voice and messaging automation

Realtime voice AI platform: top-ranked TTS-2, speech-to-speech, and zero-markup LLM routing for consumer apps.

Open-source, self-hosted voice AI platform with a visual workflow builder, MCP-native design, and bring-your-own-key model support.

AI phone answering built only for restaurants — it takes inbound calls, answers guest questions, and books reservations 24/7.

SkipCalls is a 24/7 AI receptionist that answers your existing phone line, books jobs, and blocks spam for $19.99/mo.

Resolve is an AI-native CRM built only for debt settlement teams, with six named AI workers automating intake, servicing, and negotiations.

Beckon AI admissions rep calls every career school inquiry in under a minute and books the appointment

AI-native operating system for Medicare and ACA agencies, staffing sales, retention, and revenue work with AI employees.

Notable runs healthcare AI agents that automate patient access, revenue cycle, care operations, and contact center work for health systems.

Low-latency text-to-speech API and AI voice agents — Murf AI runs real-time phone conversations at 1 cent per minute.

Real-time voice AI platform: Sonic-3.6 text-to-speech and Ink-2 speech-to-text models plus Managed Agents for building production voice agents.

Bland AI runs enterprise voice AI phone agents for regulated calls, with per-minute pricing that bundles LLM, STT, and TTS.

Vapi is an API-first platform for building voice AI agents that answer and place real phone calls at sub-500ms latency.

Build and deploy LLM voice agents with 500-600ms low latency, from no-code to low-code.

Real-time voice AI platform with sub-100ms text-to-speech, 38-language speech-to-text, and native speech-to-speech agents

Open-source voice AI framework for building real-time voice agents you host yourself

No-code AI voice agents that automate phone calls, book meetings, and handle customer interactions 24/7.

Real-time AI voice changer, cloning, TTS, and AI voice agents for gaming, content, and enterprise.

ElevenLabs turns text, audio and images into speech, music, dubbing and conversational agents, all billed from one shared credit pool.

Turbo is Bland AI's all-in per-minute voice API covering LLM, STT, and TTS in one rate

Branded, customizable AI voice ordering for restaurant chains

Modular LLM agentic AI platform that automates enterprise contact centers across voice and text in Swiss-German, German, French and Italian.