OpenVoice vs Retell AI

Side-by-side comparison of features, pricing, and ratings

Analysis reviewed Live tool data as of 2026-09-29
Cross-checked through our multi-step verification ·
Saved

At a glance

DimensionOpenVoiceRetell AI
PricingFree (open-source)Freemium; paid plans start at $X/mo (not public)
Primary Use CaseVoice cloning with style controlAI phone call automation
LatencyNot real-time (offline generation)~600ms (conversational)
CustomizationGranular control over emotion, accent, rhythmDrag-and-drop call flow, function calling, RAG
DeploymentSelf-hosted (GitHub)Cloud API
Best ForResearchers, developers building custom voice appsSupport/sales teams automating phone operations

Choose OpenVoice if you need free, open-source voice cloning with fine-grained style control and can self-host. Choose Retell AI if you need a production-ready, low-latency phone call automation platform with drag-and-drop flows and integrations. They serve completely different needs.

Try OpenVoiceTry Retell AI
OpenVoice
OpenVoice

Open-source instant voice cloning from a 10-second clip, with granular control over emotion, accent, rhythm, and intonation.

Visit Website
Retell AI
Retell AI

Retell AI builds, tests, and deploys AI phone agents on a pay-as-you-go voice platform priced from $0.07/min.

Visit Website
Pricing
Free
Freemium
Plans
$0
$0/mo (+ $10 free credits)
Custom
Popularity
15 views
6.9k views
Skill Level
Intermediate
Intermediate
API Available
Platforms
—
WebAPI
Categories
🎙️ Voice & Speech
☎️ Voice AI Agents & Phone Automation
Features
Instant voice cloning from a short reference audio clip
Accurate tone color cloning across multiple languages and accents
Granular style control over emotion (e.g. happy, sad)
Granular style control over accent (e.g. Indian, British, Australian)
Control over rhythm, pauses, and intonation
Zero-shot cross-lingual voice cloning for languages outside the training set
Mixed-lingual speech generation
Open-source source code on GitHub (myshell-ai/OpenVoice)
Technical report published on arXiv (2312.01479)
Head-to-head comparison demos against XTTS-v2 and Valle-X
No lengthy training required per speaker
Computationally efficient — the project claims tens of times lower cost than commercial voice APIs
Runs locally, so audio and reference voices stay on your own hardware
AI voice agents with ~600ms latency and proprietary turn-taking
Drag-and-drop visual conversation flow builder plus single-prompt agents
Live cost estimator itemising LLM, TTS, voice infra and telephony
Retell Workflows: native orchestration for pre-call and post-call steps
Integration library and tool store inside the Retell dashboard
Preset functions for common agent actions
Conductor copilot: scenario simulation, auto-generated regression tests, in-flow change review
Batch outbound campaigns with pacing, retries and voicemail handling
IVR navigation, DTMF capture and extension dialing
Agentic human handoff where the AI briefs the human agent before transferring
Live call monitoring with real-time transcripts and instant take-over
AI Quality Assurance scoring up to 100% of calls
Custom analytics dashboards with A/B test comparison
Post-call extraction with built-in success and sentiment scoring
Built-in CRM sync to Salesforce, HubSpot, Dynamics 365, GoHighLevel and Zoho CRM
Integrations
Twilio
Vonage
Telnyx
GoHighLevel
n8n
HubSpot
Make
Slack
Zapier
Salesforce
Zendesk
Cal.com
Calendly
Google Drive
Dynamics 365

What real users say: OpenVoice vs Retell AI

Not marketing copy and not our opinion — a structured sweep of public discussion (reviews, forums, communities and video comments), showing what people praise and what they complain about for each tool.

OpenVoice

8 mentions across 3 sources · 80% positive (averaged across 3 sources)

Hacker News, App Store, Lemmy

What users praise

  • • Free and open-source—no licensing costs for personal or commercial use.
  • • Accurate tone color cloning from a short audio clip.
  • • Granular control over emotion, accent, rhythm, and intonation.
  • • Zero-shot cross-lingual voice cloning works even for unseen languages.

What frustrates them

  • • User feedback is very sparse—hard to gauge real-world reliability.
  • • Confusion with OpenVoiceOS may mislead new users.
  • • No official support; relies on community forums and GitHub issues.
  • • Integration with AI Runner is experimental, implying potential bugs.

Researched Jul 3, 2026

Retell AI

36 mentions across 3 sources · 75% positive (averaged across 3 sources)

Hacker News, Product Hunt, Lemmy

What users praise

  • • Sub-second (~600ms) latency delivered as promised.
  • • Handles interruptions naturally — a missing feature in competitors.
  • • Sounded most natural among voice AI products tested by reviewer.
  • • Handles different accents and background noise effectively.

What frustrates them

  • • Lack of long-term user reviews; feedback is launch-day heavy.
  • • No community discussion on pricing pain points yet.
  • • Proprietary platform; no self-hosted option for full control.
  • • No critical voices in data; hidden issues unknown.

Researched Aug 18, 2026

Who should pick which

  • Voice cloning researcher
    Pick: OpenVoice

    OpenVoice provides full access to the model, code, and technical report, enabling experimentation and extension. Retell AI does not support custom voice cloning.

  • Content creator for multilingual videos
    Pick: OpenVoice

    OpenVoice allows cloning a voice and synthesizing in multiple languages with style control, free of charge. Retell AI is not designed for content generation.

  • Customer support manager handling high call volume
    Pick: Retell AI

    Retell AI automates inbound and outbound calls with low latency, drag-and-drop flows, and CRM integrations. OpenVoice cannot handle live calls.

  • Developer building a voice assistant app
    Pick: OpenVoice

    For custom voice synthesis with cloning and style control, OpenVoice offers free, self-hosted flexibility. Retell AI is a closed platform for phone calls only.

  • Sales team needing outbound lead qualification
    Pick: Retell AI

    Retell AI supports batch dialing, real-time function calling, and call analytics. OpenVoice lacks outbound calling capabilities.

Frequently Asked Questions

OpenVoice vs Retell AI: which should you choose?

Choose OpenVoice if you need free, open-source voice cloning with fine-grained style control and can self-host. Choose Retell AI if you need a production-ready, low-latency phone call automation platform with drag-and-drop flows and integrations. They serve completely different needs.

Can OpenVoice be used for real-time phone calls?

No. OpenVoice is an offline voice cloning and generation model, not designed for live conversational latency.

Does Retell AI offer voice cloning?

No. Retell AI uses pre-built neural voices; it does not clone a specific speaker from a short audio clip.

Which tool is cheaper for a startup?

OpenVoice is free (open-source). Retell AI has a free tier but paid plans incur per-minute costs; for low-volume use, OpenVoice is cheaper.

Can I customize the accent in Retell AI?

Retell AI supports multiple languages but does not provide granular accent control like OpenVoice.

Does OpenVoice integrate with telephony services?

No. OpenVoice is a model library; you would need to build telephony integration yourself.

Is OpenVoice suitable for production deployment?

Yes, with proper infrastructure (GPU servers, scaling). However, it requires DevOps effort; Retell AI is managed.

Which tool is better for multilingual support?

OpenVoice supports multiple languages and zero-shot cross-lingual cloning. Retell AI supports languages but does not clone voices across languages.

Can I try Retell AI for free?

Yes, Retell AI offers a free tier with limited usage minutes to test the platform.

More OpenVoice or Retell AI comparisons

MiniMax Audio vs Retell AI comparison

If you need a TTS API for voiceovers or customer service prompts, MiniMax Audio is the straightforward pick with its low-latency streaming and multilingual voices. If you're automating phone conversat

TurboScribe vs Retell AI comparison

If you need unlimited, high-accuracy transcription for pre-recorded audio/video in many languages, TurboScribe's freemium model (free + $10/mo unlimited) is a no-brainer. For teams automating live pho

MP3 to Text vs Retell AI comparison

Choose MP3 to Text if you need accurate, batch transcription of audio files into text with multi-language support. Choose Retell AI if you need a real-time voice agent platform for automating phone ca

TTSMaker vs Retell AI comparison

Retell AI and TTSMaker serve completely different needs. Retell AI is a powerful platform for automating phone conversations at scale, ideal for businesses that need low-latency, human-like voice agen

Typecast AI vs Retell AI comparison

If your core need is automating phone conversations (inbound/outbound calls) with low latency and function calling for real-world tasks like booking or payments, Retell AI is the clear choice. If you

Talk-to-ChatGPT vs Retell AI comparison

For individuals who want free voice access to ChatGPT on Chrome, Talk-to-ChatGPT is a simple, costless choice. For businesses needing to automate phone conversations at scale with near-human latency a

Explore each tool further

OpenVoice
View OpenVoice reviewOpenVoice alternatives
Retell AI
View Retell AI reviewRetell AI alternatives

Browse these categories

Best AI Voice & Speech toolsBest AI Voice AI Agents & Phone Automation tools
Still deciding? Get the weekly AI tools brief

One email a week — new tools, honest comparisons, no spam.

Last reviewed: July 3, 2026