Model comparison
Mercury 2 vs Yi-Lightning
Mercury 2 is the stronger model overall, scoring 39.1 to 37.1 on the Noometry Index.
Last verified . 11 shared benchmarks.
Summary
- They share 11 benchmarks with published results for both. Mercury 2 scores higher in 6 categories and Yi-Lightning in 1 category; 6 gaps are clear of the uncertainty.
- The widest gap is in coding, where Mercury 2 leads 33.5 to 27.4.
Side by side
| Mercury 2 | Yi-Lightning | |
|---|---|---|
| Provider | Inception | 01.AI |
| Noometry Index | 39.1 | 37.1 |
| Released | 2026-02-20 | 2024-12-02 |
| Weights | Proprietary | Proprietary |
| Context window | 128K | — |
| Max output | 50K | — |
| Input $ / M tokens | $0.25 | — |
| Output $ / M tokens | $0.75 | — |
| Results tracked | 17 | 18 |
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Category by category
Coding Mercury 2 leads
Mercury 2: 33.5 (#255), Yi-Lightning: 27.4 (#320)
| Benchmark | Mercury 2 | Yi-Lightning |
|---|---|---|
| LMArena Coding | 1391 | 1312 |
| Aider Polyglot | — | 12.9% |
| LMArena WebDev | 1171 | — |
| SciCode | 38.7% | — |
| WeirdML | 43.2% | — |
| ALE-Bench | 785.58 | — |
Reasoning Yi-Lightning leads
Mercury 2: 23.8 (#170), Yi-Lightning: 25.9 (#139)
| Benchmark | Mercury 2 | Yi-Lightning |
|---|---|---|
| LMArena Hard Prompts | 1362 | 1302 |
| CritPt | 0.8% | — |
Math Not comparable
Mercury 2: —, Yi-Lightning: 36.2 (#172)
| Benchmark | Mercury 2 | Yi-Lightning |
|---|---|---|
| LMArena Math | — | 1300 |
Knowledge Too close to call
Mercury 2: 36.2 (#172), Yi-Lightning: 35.4 (#185)
| Benchmark | Mercury 2 | Yi-Lightning |
|---|---|---|
| LMArena Expert | 1358 | 1286 |
| Vectara Hallucination Rate | 12.3% | — |
Multilingual Mercury 2 leads
Mercury 2: 46.6 (#157), Yi-Lightning: 42.2 (#196)
| Benchmark | Mercury 2 | Yi-Lightning |
|---|---|---|
| LMArena Non-English | 1331 | 1269 |
| LMArena Chinese | 1417 | 1320 |
| LMArena Russian | 1304 | 1255 |
| LMArena French | — | 1305 |
| LMArena German | — | 1267 |
| LMArena Japanese | — | 1228 |
| LMArena Korean | — | 1192 |
| LMArena Spanish | — | 1315 |
Instruction Following Mercury 2 leads
Mercury 2: 70.2 (#165), Yi-Lightning: 67.4 (#196)
| Benchmark | Mercury 2 | Yi-Lightning |
|---|---|---|
| LMArena Instruction Following | 1329 | 1278 |
Long Context Mercury 2 leads
Mercury 2: 40.5 (#154), Yi-Lightning: 39.4 (#181)
| Benchmark | Mercury 2 | Yi-Lightning |
|---|---|---|
| LMArena Longer Query | 1330 | 1297 |
Writing & Preference Mercury 2 leads
Mercury 2: 53.8 (#155), Yi-Lightning: 50.2 (#184)
| Benchmark | Mercury 2 | Yi-Lightning |
|---|---|---|
| LMArena Text | 1355 | 1302 |
| LMArena Creative Writing | 1289 | 1280 |
| LMArena Multi-Turn | 1358 | 1311 |
Frequently asked questions
Is Mercury 2 better than Yi-Lightning?
Mercury 2 is the stronger model overall, scoring 39.1 to 37.1 on the Noometry Index.
Is Mercury 2 or Yi-Lightning better for coding?
Mercury 2 scores higher on coding benchmarks: 33.5 versus 27.4 in the Noometry coding category.
How many benchmarks do Mercury 2 and Yi-Lightning share?
11 benchmarks have published results for both models. Mercury 2 has 17 scored results on Noometry and Yi-Lightning has 18.