IndexTTS2
Emotional zero-shot TTS with precise duration control.
About
IndexTTS2 is Bilibili IndexTeam's second-generation open TTS, notable as an early autoregressive TTS model with precise synthesis-duration control alongside highly expressive, emotion-controllable speech. Emotions can be steered through multiple input modalities, including natural-language descriptions.
The team reports it outperforming existing zero-shot TTS on word error rate, speaker similarity, and emotional fidelity. Commercial use requires contacting the team, and community discussion leans heavily on Chinese-language channels.
Specs
Context window
Pricing
Free quota
API access
Weights
Released
Benchmarks
Provider-reported unless a source says otherwise. Benchmarks are marketing-adjacent by nature — treat them as directional.
Use cases
Trust score — 7/10
Scored 7/10 (metrics tier, metrics-v1). Evidence: Release date (2025-09-08) from official changelog via open-dubbing refer-docs; mirrors corroborate June 2025 announcement; SOTA claims are team-reported; community discussion mostly Chinese-language; Manual review: notable duration-control feature; commercial use needs team contact. License: Open weights; commercial use requires contacting indexspeech@bilibili.com.
How the trust score is built
Full methodology →- Adoption · stars/downloads, log-scaled vs peers
- 6.0/10
- Maintenance · recency, releases, issue load
- 7.0/10
- Openness · license + docs
- 7.0/10
- Manual review · sanity read + red-flag check
- 7.0/10
- · Release date (2025-09-08) from official changelog via open-dubbing refer-docs; mirrors corroborate June 2025 announcement
- · SOTA claims are team-reported; community discussion mostly Chinese-language
- · Manual review: notable duration-control feature; commercial use needs team contact