Sesame CSM

Open Apache-2.0 conversational speech model generating context-aware, natural speech

What Sesame CSM does

  • Open Apache-2.0 conversational speech model generating context-aware, natural speech
  • Takes prior dialogue turns as context for prosody
  • Weights on Hugging Face; base for the Sesame voice companion

Sesame CSM — straight answers

What is Sesame CSM?

Sesame CSM is listed under AI Voice & Speech, in the Content & Media Generation category on Flocci AI Tools. Open Apache-2.0 conversational speech model generating context-aware, natural speech. It is free, with no paid plan attached, and it lives at github.com.

Is Sesame CSM free?

Sesame CSM is listed as fully free — there is no paid tier attached to it in the catalog. That makes it one of the 397 entries on Flocci AI Tools with no upgrade path built in.

Can I use Sesame CSM in a browser, or is there an app?

Sesame CSM needs to be installed or self-hosted — it doesn't run in a browser tab. It is available on self-hosting.

What can Sesame CSM do?

Sesame CSM does 3 things the catalog singles out: Open apache-2.0 conversational speech model generating context-aware, natural speech; takes prior dialogue turns as context for prosody; weights on hugging face; base for the sesame voice companion.

What is the best free alternative to Sesame CSM?

Copilot Audio Expressions is the closest free alternative: it sits in the same AI Voice & Speech sub-category and is free. Kokoro Web, Zonos and Chatterbox (Resemble AI) also start free. The full list is on the alternatives page.

See the full list →

Sesame CSM alternatives

Compare all alternatives →

ElevenLabs

AI Voice & Speech
freemium
  • Most natural text-to-speech and voice cloning
  • Dubbing into 30+ languages
  • Voice design and a huge voice library
  • Free monthly characters

Murf AI

AI Voice & Speech
trial
  • Studio-quality voiceovers for videos
  • Sync voice with slides and media
  • Voice changer and cloning
  • Free trial minutes

Cartesia

AI Voice & Speech
freemium
  • Ultra-low-latency real-time voice (Sonic)
  • Ideal for voice agents and calls
  • Instant voice cloning
  • Free tier for developers

Hume AI

AI Voice & Speech
freemium
  • Emotionally expressive voice interface (EVI)
  • Detects and responds to tone
  • Customizable empathic voices
  • Free developer credits

Fish Audio

AI Voice & Speech
freemium
  • 15-second voice cloning claimed near-perfect fidelity
  • S2.1 Pro real-time emotionally-controllable voice model, free to start for devs
  • Bundles TTS, voice cloning, STT and a full voice-agent stack in one platform

Speechify

AI Voice & Speech
freemium
  • Free tier includes unlimited basic TTS at up to 1.5x speed with 10 voices
  • Scan & Listen turns physical text/photos into audio
  • AI Podcasts and Voice AI Assistant bundled into Premium beyond plain reading

Head-to-head comparisons