Smallest.ai · Proprietary · Read 2026-10-27
Smallest.ai Lightning V3.1 Pro (Jul 2026): latency, voice quality, price and languages
- Rank
- 20 / 23
- Speed tier
- Visible delay
- P95
- 703.3 ms
- Price / 1M chars
- $19.50
Smallest.ai Lightning V3.1 Pro (Jul 2026) is a proprietary text-to-speech model from Smallest.ai. Coval measures a median of 360.5 ms and a P95 of 703.3 ms to first audio, which puts it in the Visible delay speed tier, rank 20 of 23 in the multilingual ranking. No source tested it in a language other than English.
This summary is generated from the measures below; it is not a vendor description. Measures a source does not hold are shown as n/a and are never estimated.
Speed (Coval, 30 days, US East, English)
| Speed tier | Visible delay |
| Median time to first audio | 360.5 ms |
| P90 | 586.0 ms |
| P95 | 703.3 ms |
| Mean | 397.0 ms |
| Standard deviation | 139.9 ms |
| Calls in the window | 2,797 |
| Cekura median, streamed text | n/a |
| Cekura median, full text | n/a |
Voice quality (never added together)
| Listener Elo (Artificial Analysis) | 1,169 ±12 |
| Customer-service Elo (Artificial Analysis) | 1,189 ±24 |
| Naturalness (Speko) | 1,447 |
| Naturalness estimate (Cekura, 1 to 5) | n/a |
Accuracy
| Reading accuracy (Cekura) | n/a |
| Numbers (Cekura) | n/a |
| Codes (Cekura) | n/a |
| Context (Cekura) | n/a |
| Medical terms (Cekura) | n/a |
| Hard passages judged correct (Artificial Analysis) | 72.1% |
| Numbers and dates (Speko score) | n/a |
| Word error rate (Coval) | 1.6% |
Price per 1 million characters
| Range across sources | $19.50 |
| Artificial Analysis | $19.50 |
| Speko | $19.50 |
| Coval | $19.50 |
| Cekura | n/a |
Coverage
| Access | Proprietary |
| Streaming | Measured |
| Coval tags | multilingual, voice-cloning |
| Rated for | Knowledge sharing, Assistants, Entertainment, Customer service |
| Languages tested | none beyond English |
Not collected
- Numbers and dates (Speko pronunciation score): listed by Speko without this value (reading of 2026-10-27)
Sources
- https://artificialanalysis.ai/text-to-speech (read 2026-10-27)
- https://artificialanalysis.ai/text-to-speech/leaderboard/provider-voice (read 2026-10-27)
- https://benchmarks-api-6wxgp27p2a-ue.a.run.app/v1/results/aggregates?benchmark=TTS&window=30d&include_series=false (read 2026-10-27)
- https://benchmarks.speko.ai/tts/ (read 2026-10-27)
- Vendor site: https://smallest.ai/
Keep exploring
Frequently asked questions
- How fast is Smallest.ai Lightning V3.1 Pro (Jul 2026)?
- Coval measures a median time to first audio of 360.5 ms and a P95 of 703.3 ms for Smallest.ai Lightning V3.1 Pro (Jul 2026), over 30 days from the US East in English (Visible delay tier).
- How much does Smallest.ai Lightning V3.1 Pro (Jul 2026) cost?
- The benchmarks print a list price of $19.50 per million characters for Smallest.ai Lightning V3.1 Pro (Jul 2026).
- Which languages was Smallest.ai Lightning V3.1 Pro (Jul 2026) tested in?
- No source tested Smallest.ai Lightning V3.1 Pro (Jul 2026) in a language other than English.