Retell AI vs Ultravox

Retell AI is freemium — a usable free tier with paid plans above it. Ultravox is freemium — a usable free tier with paid plans above it. Both are listed under Real-Time Voice Agents, so this is a like-for-like comparison. Neither is ranked above the other — Flocci carries no sponsored placement.

Retell AI vs Ultravox — straight answers

Retell AI vs Ultravox: what is the difference?

Retell AI is freemium — a usable free tier with paid plans above it and is listed for free starting credit with no contract required. Ultravox is freemium — a usable free tier with paid plans above it and is listed for speech-native processing skips the STT-to-text bottleneck, preserving tone/cadence/pitch. Both sit in Real-Time Voice Agents.

Is Retell AI or Ultravox cheaper to start with?

Neither — Retell AI and Ultravox are both freemium, so the choice comes down to capability rather than cost. Both entries list what they uniquely do above.

Which should I choose, Retell AI or Ultravox?

Choose Retell AI if you need free starting credit with no contract required; choose Ultravox if you need speech-native processing skips the STT-to-text bottleneck, preserving tone/cadence/pitch. Flocci AI Tools does not rank one above the other — it shows both feature sets side by side and lets the requirement decide.

Retell AI compared with Ultravox: pricing tier, category, listed capabilities and links.
 Retell AIUltravox
Pricing tierFree tier + paid plansFree tier + paid plans
Free to startYesYes
CategoryAI Agents & AutomationAI Agents & Automation
TypeReal-Time Voice AgentsReal-Time Voice Agents
Listed capabilities
  • Free starting credit with no contract required
  • Supports swapping GPT, Claude or Gemini as the reasoning layer per agent
  • Batch calling campaigns plus live AI-to-human call transfer built in
  • Speech-native processing skips the STT-to-text bottleneck, preserving tone/cadence/pitch
  • Free tier: 5¢/min including TTS for up to 5 concurrent calls
  • Open-weight models (fixie-ai) published on Hugging Face for research use
Tagsretell ai, ai phone agent, voice agent platform, call center ai, conversational voice ai, free creditsultravox, speech native voice ai, real time voice model, low latency voice agent, open weight voice model, free
Websiteretellai.comultravox.ai
Full pageRetell AI details →Ultravox details →
AlternativesRetell AI alternatives →Ultravox alternatives →

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