Comparison · read on October 27, 2026
Gradium TTS vs Smallest.ai Lightning V3.1 Pro (Jul 2026)
Two text-to-speech (TTS) models side by side, from four public benchmarks. Speed comes first, then listener rating and price; the three are never added into a score.
| Measure | Gradium TTS | Smallest.ai Lightning V3.1 Pro (Jul 2026) |
|---|---|---|
| Provider | Gradium | Smallest.ai |
| Speed tier | Headroom | Visible delay |
| P95 time to first audio | 104.3 ms | 703.3 ms |
| Median time to first audio | 53.7 ms | 360.5 ms |
| Listener Elo | 1,174 | 1,169 |
| Price per 1M characters | $36 to $57.8 | $19.5 |
| Access | Proprietary | Proprietary |
| Rank in the full ranking | 2 | 27 |
| Rank by use case | Customer service 1, Voice agents 2, Assistants 1, Entertainment 1, Knowledge sharing 1 | Customer service 17, Assistants 17, Entertainment 17, Knowledge sharing 17 |
Which should you choose?
- Speed: Gradium TTS comes out ahead (104.3 ms against 703.3 ms at P95).
- Listener rating: Gradium TTS and Smallest.ai Lightning V3.1 Pro (Jul 2026) are a tie (Elo 1,174 against 1,169; scores within each other's 95% intervals are a tie).
- Price: Smallest.ai Lightning V3.1 Pro (Jul 2026) comes out ahead ($36 to $57.8 against $19.5 per million characters, lowest list price).
Where a model is not timed or not rated, nothing is estimated. See each model page for its sources: Gradium TTS and Smallest.ai Lightning V3.1 Pro (Jul 2026).
Frequently asked questions
- Which is faster, Gradium TTS or Smallest.ai Lightning V3.1 Pro (Jul 2026)?
- Speed: Gradium TTS comes out ahead (104.3 ms against 703.3 ms at P95).
- Which is rated higher by listeners, Gradium TTS or Smallest.ai Lightning V3.1 Pro (Jul 2026)?
- Listener rating: Gradium TTS and Smallest.ai Lightning V3.1 Pro (Jul 2026) are a tie (Elo 1,174 against 1,169; scores within each other's 95% intervals are a tie).
- Which is cheaper, Gradium TTS or Smallest.ai Lightning V3.1 Pro (Jul 2026)?
- Price: Smallest.ai Lightning V3.1 Pro (Jul 2026) comes out ahead ($36 to $57.8 against $19.5 per million characters, lowest list price).
- Why is this model always on the left?
- Gradium TTS is the reference model of this site's comparison pages: it is set against every other listed model. The editor chose it; it is not chosen by rank.