Speech Arena Elo 1,049 on Artificial Analysis, latency not measured; ranked 69th (tied) of 112 in the TTS for Voice Agents 2026 index.
Benchmark summary: 5.8/100, ranked 69th (tied) of 112 in the TTS for Voice Agents 2026 index (Listed). Strongest criterion: price, 2.1 of 5 points.
async Flash v1.0 is a proprietary text-to-speech (TTS) API from Async, measured by one independent benchmark, Artificial Analysis.
Overall score
5.8 /100
Data checked on September 30, 2026
Updated after each benchmark capture
Every point comes from a public benchmark: sources · methodology
async Flash v1.0 ranks 69th of 112 in the 2026 text-to-speech (TTS) API benchmark, with a score of 5.8/100.
Neither Coval nor Speko measures async Flash v1.0's latency, so it scores 0 of 60 on real-time speed and does not appear in the real-time ranking.
No accuracy measurement: Coval does not measure its word error rate and Speko does not rate its pronunciation robustness, so accuracy counts 0 of 15.
In the Artificial Analysis Speech Arena (capture of October 1, 2026), async Flash v1.0 has an Elo of 1,049 (±12, 95% confidence) from 3,962 blind comparisons, 58th highest of the 92 models Artificial Analysis rates.
Artificial Analysis lists async Flash v1.0 at $10.1 per 1M characters (12th lowest of the 78 models Artificial Analysis lists a price for).
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StepFun Step Audio EditX (Mar 2026) is an open-weights text-to-speech (TTS) API from StepFun, measured by one independent benchmark, Artificial Analysis.