whatmodel.sh / tts / IndexTTS-2

IndexTTS-2 is an open-weights text-to-speech model from IndexTeam (bilibili), released September 2025. Licence: bilibili-model-use-license.

Catalogue identity notes

IndexTeam/IndexTTS-2 (RW-Voice-EQ ran it via Replicate lucataco/indextts-2; Boson column 'IndexTTS-2').

Model information sources

Release date ↗ · Weights licence ↗

63.2±1.3#25 of 118 text-to-speech modelsfrom 28 benchmark results across 8 sources

Score within the Vapi Humanness · Bradley–Terry rating, 2026-09-25 snapshot comparison set only.

$ how it compares

The text-to-speech models ranked either side of IndexTTS-2, out of 148 with a score, then more from IndexTeam (bilibili).

#modelscorewhereRAMreleased
30Eleven Turbo v2.5 ElevenLabs64±4api $50.00/M chars2024-07
31Fish Audio S2.1 Pro Fish Audio63±3api $15.00/M chars2026-06
32IndexTTS-2 IndexTeam (bilibili)63±1local~8.9GB2025-09
33MOSS-TTS v1.5 (8B) OpenMOSS63±2local~24GB2026-05
34GLM-TTS Z.ai63±2local~8.9GB2025-12
more from IndexTeam (bilibili)
39IndexTTS (v1) IndexTeam (bilibili)62±3local~1.2GB2025-03

see all text-to-speech models · find the ones that fit your machine

$ what it's good at

voice cloning▁·▁▁▁▁▁▁▇█▃▃ #17 of 37 · 46% of its score · 5 tests

Beats Gemini 3.1 Flash TTS Preview, Fun-CosyVoice3-0.5B-2512 here, though they rank higher overall. Trails Qwen3-TTS 12Hz 0.6B Base, F5-TTS v1 Base, IndexTTS (v1) here, though they rank lower overall.

testresultvs the others in its rundifficultycountswhy
Seed-TTS test-en · speaker similarity (WavLM-large SV) +270.4% ✎█·█·██·▄·▄·▄ beats 5/10medium · avg 53%▇▇▇▇▇▇▇ 18%at its level · several runs
Seed-TTS test-zh · speaker similarity (WavLM-large SV) +176.0% ✎▃··▃█▅▅··▃·▃ beats 3/10medium · avg 62%▇▇▇▇ 11%several runs
Seed-TTS test-en · Whisper large-v3 WER +22.1% ✎▃··▃▅··▅·█▃▅ beats 5/11avg 3.6%▇▇▇ 7.5%blunt · several runs
Seed-TTS-Eval · test-en/test-zh macro mean error1.6% ✎▄··▄▄····█▄▄ beats 2/6avg 3.7%▇▇ 5.1%typical
Seed-TTS test-zh · Paraformer CER +11.0% ✎▂··▄··▂▂█·▄▂ beats 6/11avg 2.1%▇ 3.7%blunt · several runs
other tests17 not in a task · 53% of its score
testresultvs the others in its rundifficultycountswhy
CV3-Eval hard-en · WER8.6% ✎█··██·██████ beats 4/8avg 26%▇▇▇▇ 10%sharp
CV3-Eval ZH (zero-shot Chinese) · CER3.6% ✎█▄···█▄·█··▄ beats 3/8avg 9.2%▇▇▇ 7.9%typical
CV3-Eval hard-zh · CER8.7% ✎▃▃·▃··▃▃█··▃ beats 4/8avg 23%▇▇▇ 6.4%typical
CV3-Eval hard-en · speaker similarity (ERes2Net SV)74.0% ✎▄█▄·▄··▄··▄█ beats 7/8medium · avg 49%▇▇ 6.0%at its level
VoxCPM listening test · Chinese speaker-similarity MOS (S-MOS)4.05 / 5 ✎█·······██·█ beats 2/3medium · avg 3.29 / 5▇▇ 4.3%typical
VoxCPM listening test · English speaker-similarity MOS (S-MOS)4.16 / 5 ✎██········██ beats 2/3medium · avg 3.43 / 5▇▇ 4.1%typical
VoxCPM listening test · English naturalness MOS (N-MOS)4.03 / 5 ✎█······█··██ beats 1/3medium · avg 3.36 / 5▇▇ 3.9%typical
VoxCPM listening test · Chinese naturalness MOS (N-MOS)4.25 / 5 ✎██·······█·█ beats 3/3medium · avg 2.85 / 5▇ 3.4%sharp · at its level
9 more tests
testresultvs the others in its rundifficultycountswhy
CV3-Eval EN (zero-shot English) · WER4.3% ✎▃·······▃▅█▅ beats 7/8avg 16%▇ 2.6%noisy
SAP voice reconstruction · human BWS reconstruction preference1167.3 ✎█▄█····▄··▄▄ beats 7/7avg 995▇ 1.8%typical
MiniMax multilingual test set · 23-language mean error112.9% ✎▃·▃·▃·····▃█ beats 0/6avg 44%▇ 1.1%sharp · noisy
CV3-Eval multilingual voice clone · 9-language mean error129.3% ✎▃·····▃···▅█ beats 0/6avg 20%▇ 0.8%noisy
RW-Voice-EQ TTS · Long-Form Stability (human)3.52 / 5 ✎█······█·███ beats 2/4medium · avg 3.42 / 5▇ 0.4%blunt · at its level
CodecMOS-Accent VCTK voice clone · human naturalness MOS (S-NAT)3.98 / 5 ✎█··▄▄██▄·▄▄▄ beats 7/11easy · avg 3.99 / 5▇ 0.3%blunt
CodecMOS-Accent VCTK voice clone · human speaker-similarity MOS (S-SPK-SIM)4.53 / 5 ✎▄▄█·▄▄▄▄▄·▄█ beats 10/11easy · avg 4.20 / 5▇ 0.3%blunt
SAP voice reconstruction · TTSDS dual-reference distributional score86.1% ✎▄····▄▄▄▄▄·█ beats 6/7very easy · avg 86%▇ 0.3%blunt
SAP voice reconstruction · WER of reconstructed speech (Whisper turbo)9.9% ✎▄▄▄··█▄··▄·▄ beats 6/7avg 17%▇ 0.0%blunt · noisy

$ where to run it

Other ways to run it

  1. Run it as published · needs ~8.86 GB · from github.com/index-tts
    git clone https://github.com/index-tts/index-tts.git && cd index-tts && pip install -U uv && uv sync && uv tool install "huggingface-hub" && hf download IndexTeam/IndexTTS-2 --local-dir=checkpoints_2 && uv run python -c "from indextts.utils.examples_downloader import ensure_examples_available; ensure_examples_available()" && PYTHONPATH="$PYTHONPATH:." uv run python -c "from indextts.infer_v2 import IndexTTS2; tts = IndexTTS2(cfg_path='checkpoints_2/config.yaml', model_dir='checkpoints_2', use_fp16=False, use_cuda_kernel=False, use_deepspeed=False); tts.infer(spk_audio_prompt='examples/voice_01.wav', text='Translate for me, what is a surprise!', output_path='gen.wav', verbose=True)"

Official weights and documentation: huggingface.co/IndexTeam ↗

$ how the score was worked out · UltraEval-Audio (OpenBMB) · T… 53%, VoxCPM: Tokenizer-Free TTS fo… 16%, OmniVoice: Towards Omnilingua… 11% and 5 more

Each result implies a score on its own, after adjusting for how hard its test is and who ran it. The score is their weighted average, with a small pull toward the middle for thinly tested models. Each test's weight is its counts column above; here it's added up by who ran the tests. How it works

$ improve this page

Use a short GitHub form or edit the data through a pull request. Every number needs a source; here's which ones we can use.

data updated · sources and licences · json