Lightning V3.1 Pro (Oct 2026) text-to-speech model
Smallest.ai
Lightning V3.1 Pro (Oct 2026) is a text-to-speech (TTS) model from Smallest.ai. It ranks #8 of 99 on the Artificial Analysis TTS arena with Elo 1266 (95% CI ±16, – samples).
Key facts
- Provider
- Smallest.ai
- AA rank
- #8 / 99
- AA Elo (95% CI)
- 1266 ±16
Not yet available: AA samples, TTS Arena Elo (uncertainty), TTS Arena votes, TTS Arena win rate, Price (per 1M chars), Released, Open weights, License, Voices tested by AA, Languages, Voice cloning
Who it is for (from the data)
- Best-quality seekers: #8 of 99 on Artificial Analysis, in the top 10.
- Use via Smallest.ai's service or API; the sources do not list it as open weights.
- Existing Smallest.ai users: this vendor has 3 models on the board.
Nearby models
By AA Elo; this model highlighted| # | Model | AA Elo | Arena Elo | Price $/1M chars | Open weights | Δ |
|---|---|---|---|---|---|---|
| 5 |  Gemini 3.8 Flash TTS Google | 1283 | – | $16.5 | – | +17 |
| 6 |  Qwen-Audio-3.0-TTS-Plus Alibaba | 1269 | – | $19.3 | – | +3 |
| 7 | IRealtime TTS-2 Inworld | 1267 | – | $20.8 | – | +1 |
| 8 | SLightning V3.1 Pro (Oct 2026) Smallest.ai | 1266 | – | – | – | |
| 9 | Gemini 3.8 Flash-Lite TTS Google | 1259 | – | $11 | – | -7 |
| 10 | SSimba 3.2 SpeechifyAI | 1249 | – | $6.6 | – | -17 |
| 11 |  Fish Audio Drama 3 Preview Fish Audio | 1240 | – | $15 | Open | -26 |
Alternatives · More from Smallest.ai
| # | Model | AA Elo | Arena Elo | Price $/1M chars | Open weights |
|---|---|---|---|---|---|
| – | SLightning v3.1 Pro Smallest.ai | – | 1525 | – | – |
| 80 | SLightning v3.1 Smallest.ai | 1022 | – | $25 | – |
Alternatives · Top 5 open-weight by AA Elo
| # | Model | AA Elo | Arena Elo | Price $/1M chars | Open weights |
|---|---|---|---|---|---|
| 11 | Fish Audio Drama 3 Preview Fish Audio | 1240 | – | $15 | Open |
| 12 | BBreeze TTS 2 BreezeBlue | 1228 | – | $34 | Open |
| 23 |  Ming-3.0-tts Ant Group | 1187 | – | – | Open |
| 39 | Fish Audio S2 Pro Fish Audio | 1109 | – | $15 | Open |
| 42 |  Step Audio EditX (Mar 2026) StepFun | 1099 | – | – | Open |
How to read the scores
- AA Elo: the Elo score from the Artificial Analysis speech arena. Listeners blind-compare two clips and pick the better one; "±" is the 95% confidence interval.
- TTS Arena Elo: Elo from TTS Arena V2 community blind votes. The two boards use different scales, so do not subtract one from the other.
- If the gap between two models is smaller than their combined intervals, the order is not statistically reliable; treat them as the same tier. More samples or votes mean narrower intervals.
FAQ
Where does Lightning V3.1 Pro (Oct 2026) rank among TTS models?
As of Oct 29, 2026, Lightning V3.1 Pro (Oct 2026) ranks #8 of 99 on the Artificial Analysis TTS leaderboard with Elo 1266 (±16).
Is Lightning V3.1 Pro (Oct 2026) open source?
The sources do not list Lightning V3.1 Pro (Oct 2026) as open-weight; it is generally used through the Smallest.ai API.
Which top-10 TTS model is cheapest?
Among the AA top 10, the lowest list price is Simba 3.2 (SpeechifyAI) at $6.6 per 1M characters, Elo 1249.
What is the best open-source TTS model?
By AA Elo, the top open-weight model is Fish Audio Drama 3 Preview by Fish Audio (Elo 1240, #11 overall); 18 open-weight models have an AA score.
Who makes Lightning V3.1 Pro (Oct 2026)?
Lightning V3.1 Pro (Oct 2026) is made by Smallest.ai.
How far is Lightning V3.1 Pro (Oct 2026) from #1?
#1 on Artificial Analysis is Eleven v4 Turbo (Elo 1336); Lightning V3.1 Pro (Oct 2026) has Elo 1266, 70 points behind.
Sources
17NAS syncs the upstream leaderboards daily; this page's data was synced on Oct 29, 2026.
"–" means the upstream sources do not provide this value; we do not guess.