Sand-Glass (Prompted Compression) - Chinese-Spanish In-Bounds Rate: leaderboard

Sand-Glass (Cui, Yu et al., Bilibili, 2026) tests translation for dubbing under duration limits: 1,000 colloquial Mandarin video-transcript segments, in the prompted-compression setting where the prompt gives the source syllable count and the target band for the target/source syllable ratio. Translation into Spanish must land in the 1.0-1.1 band; the score is the percentage of translations inside it, averaged over three runs; higher is better.

Metric: In-bounds rate (% of translations whose target/source syllable ratio falls in the 1.0-1.1 band; Zh-Es; 1,000 Mandarin video-transcript segments, prompt gives the source syllable count and target ratio band, mean of 3 runs). Source: arxiv.org. Saturation forecast: Around February 2027. 4 models tracked.

Top models

#ModelScoreOverall rank
1GPT-5 (Low)62.6#163 (GPT-5)
2Claude Opus 4.126.6#268

No result here: #1 Claude Fable 5.2, #2 Gemini 4 Carbon, #5 Claude Opus 5.5.

Interactive version: theaggregate.ai/benchmark?slug=sand-glass-prompted-compression-chinese-spanish-in-bounds-rate · How It Works · Data refreshed daily, snapshot 2026-11-12.