LiT (Lost in Translation) - Informal Text: leaderboard

Metric: MQM>=80 rate (%): share of round-trip translations whose back-translation to English scores at least 80 on an MQM error scale (minor -1, major -5, critical -25) from a Grok 4.1 Fast judge comparing it with the English source; each passage is translated serially through a four-language sequence and back, averaged over eight sequences (high, medium and low-resource languages); informal passages (slang, idioms, colloquial register); higher is better. Source: arxiv.org. Saturation forecast: Around January 2027. 22 models tracked.

Top models

#ModelScore
1Gemma 4 31B (IT)56.9
2Gemma 4 31B (IT) (Thinking)55.9
3Kimi K2 (Thinking)47.2
4Qwen 3.5 397B A17B (Non-reasoning)46.9
5GLM-545.9
6Qwen 3.5 397B A17B45
7DeepSeek V3.2 Exp (Non-reasoning)36.6
8GLM-5 (Non-reasoning)33.1
9Gemma 3 27B (IT)32.8
10Kimi K232.1
11GLM-4.731.6
12DeepSeek V3.2 Exp (Thinking)27.8
13Qwen 3 235B A22B 2507 Instruct25.3
14Qwen 3 235B A22B 2507 (Thinking)22.8
15Qwen 3.5 35B A3B15.9

Interactive version: theaggregate.ai/benchmark?slug=lit-lost-in-translation-informal-text · How It Works · Data refreshed daily, snapshot 2026-10-07.