Sesame CSM

Sesame
class A research

Sesame's open-weights (Apache-2.0) 1B conversational speech base model; English-focused, produces varied voices from context audio, no packaged clone.

Layer 1 — factual axes

API & price self-host only (open weights) official source ↗ 2026-07-04
Voices any (design) official source ↗ 2026-07-04
Voice cloning no (contextual matching, not packaged clone) official source ↗ 2026-07-04
Languages 1 (English) official source ↗ 2026-07-04
Weights open · Apache-2.0 official source ↗ 2026-07-04
Free tier open self-host official source ↗ 2026-07-04

Layer 2 — output quality

No independent measure yet. We publish a quality figure only when a named external benchmark ranks this model — we don’t invent one.

Eligible for Open-weightsBest free

Sesame’s open-weights (Apache-2.0) 1B conversational speech base model; English-focused, produces varied voices from context audio, no packaged clone.

Data as of 2026-07-04 · verified 2026-07-04. One ruler for all tools. How we measure ↗