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Cartesia
S
OpenAI Voice / Realtime
S
Play.ht
A
TaglineUltra-low-latency voice. Built for realtime agents.ChatGPT's voice + the Realtime API for developers.Enterprise-grade TTS with voice cloning.
Categoryvoicevoicevoice
PricingFree tier + usage-based APIVoice included with ChatGPT Plus; Realtime API by usageFree + $39-$99/mo
Best forDevelopers building voice agents, phone bots, interactive apps.Voice chat users, developers building voice agents on OpenAI.Podcasters + enterprises where cost matters.
Strengths
  • < 90ms latency — the fastest in the market
  • Sonic model sounds natural
  • Developer-friendly API
  • Advanced Voice Mode feels genuinely conversational
  • Realtime API enables true two-way voice apps
  • Built into ChatGPT
  • Strong API + enterprise features
  • Good voice variety
  • Lower cost than ElevenLabs at scale
Weaknesses
  • Fewer voices than ElevenLabs
  • Less consumer-facing brand
  • Pricey for production apps
  • Less voice variety than ElevenLabs
  • Platform lock-in
  • Voice realism slightly behind ElevenLabs
  • UX less polished
Kai's verdictS-tier for realtime. If latency matters more than voice catalog, start here.S-tier for conversation. A-tier for TTS. Complement to ElevenLabs, not replacement.A-tier. Great price/performance. Go here if ElevenLabs is too expensive.
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