EnglishOfficial IndexTeam reference
voice_01.wav
Translate for me, what is a surprise!
- Reference
- IndexTeam
- Emotion
- Follow reference / neutral
- Works with
- IndexTTS2 and IndexTTS 2.5
Model comparison
IndexTTS2 and IndexTTS 2.5 are both available on IndexTTS Online, but they fit different needs. Compare the controls exposed here, supported target languages, and official IndexTeam reference examples before choosing a model.
These rows describe controls currently exposed by IndexTTS Online. They are product capabilities, not subjective quality scores.
| Capability | IndexTTS2 | IndexTTS 2.5 |
|---|---|---|
| Hosted on IndexTTS Online | Yes | Yes |
| Target languages exposed here | Chinese, English | Chinese, English, Japanese, Spanish, Arabic |
| Explicit language selector | No | Yes |
| Emotion presets | Natural, Happy, Sad, Angry, Calm | Natural, Happy, Sad, Angry, Calm |
| Pace control exposed here | No | Faster, Normal, Slower |
Official references
English and Chinese are useful side-by-side reference languages because both hosted models support them. The audio below comes from the official IndexTeam example corpus and remains clearly attributed to its upstream source.
Translate for me, what is a surprise!
这个呀，就是我们精心制作准备的纪念品，大家可以看到这个色泽和这个材质啊，哎呀多么的光彩照人。
Source note: the reference recordings above are upstream IndexTeam demo assets. IndexTTS Online provides comparison context and hosted tools but does not claim ownership of those recordings.
Upstream evidence
The upstream IndexTTS 2.5 Technical Report reports a 2.28× improvement in real-time factor while maintaining comparable word error rate and speaker similarity to IndexTTS2. It also describes broader multilingual coverage and architectural changes intended to reduce inference cost.
This is an upstream published result, not a measurement produced by IndexTTS Online. Hardware, runtime, prompts, and serving infrastructure can change observed latency.
Product guidance
Choose IndexTTS2 when your target text is English or Chinese and you want the simpler hosted model path with the same core voice-cloning workflow.
Choose IndexTTS 2.5 when you need Japanese, Spanish, or Arabic target text, an explicit language selector, or pace controls in addition to the shared emotion presets.
If both models fit your language, use the same reference and target text in Voice Lab and choose the result that works better for your use case.
Keeping the speaker reference identical makes it easier to hear model differences instead of recording differences.
The same wording and punctuation gives both models the same speaking task.
When comparing emotion or pace, avoid changing several settings at once.
Focus on pronunciation, speaker similarity, prosody, stability, and audible artifacts for your own use case.