Model comparison
GPT-5.1-Codex vs Yi-Lightning
GPT-5.1-Codex is the stronger model overall, scoring 38.6 to 37.1 on the Noometry Index.
Last verified . 0 shared benchmarks.
Summary
- The widest gap is in coding, where GPT-5.1-Codex leads 41.9 to 27.4.
Side by side
| GPT-5.1-Codex | Yi-Lightning | |
|---|---|---|
| Provider | OpenAI | 01.AI |
| Noometry Index | 38.6 | 37.1 |
| Released | 2025-11-12 | 2024-12-02 |
| Weights | Proprietary | Proprietary |
| Context window | 400K | — |
| Max output | 128K | — |
| Input $ / M tokens | $1.25 | — |
| Output $ / M tokens | $10 | — |
| Results tracked | 6 | 18 |
Sponsored placements are available on pages like this one. Advertise on Noometry
Category by category
Coding GPT-5.1-Codex leads
GPT-5.1-Codex: 41.9 (#116), Yi-Lightning: 27.4 (#320)
| Benchmark | GPT-5.1-Codex | Yi-Lightning |
|---|---|---|
| SWE-bench Verified (bash only) | 66% | — |
| Aider Polyglot | — | 12.9% |
| LMArena WebDev | 1337 | — |
| LMArena Coding | — | 1312 |
| ALE-Bench | 1,245 | — |
Agentic & Tool Use Not comparable
GPT-5.1-Codex: 38.0 (#33), Yi-Lightning: —
| Benchmark | GPT-5.1-Codex | Yi-Lightning |
|---|---|---|
| Terminal-Bench | 60.4% | — |
| METR Time Horizons | 70.8% | — |
Reasoning Not comparable
GPT-5.1-Codex: —, Yi-Lightning: 25.9 (#139)
| Benchmark | GPT-5.1-Codex | Yi-Lightning |
|---|---|---|
| LMArena Hard Prompts | — | 1302 |
Math Yi-Lightning leads
GPT-5.1-Codex: 30.3 (#235), Yi-Lightning: 36.2 (#172)
| Benchmark | GPT-5.1-Codex | Yi-Lightning |
|---|---|---|
| ProofBench | 9% | — |
| LMArena Math | — | 1300 |
Knowledge Not comparable
GPT-5.1-Codex: —, Yi-Lightning: 35.4 (#185)
| Benchmark | GPT-5.1-Codex | Yi-Lightning |
|---|---|---|
| LMArena Expert | — | 1286 |
Multilingual Not comparable
GPT-5.1-Codex: —, Yi-Lightning: 42.2 (#196)
| Benchmark | GPT-5.1-Codex | Yi-Lightning |
|---|---|---|
| LMArena Non-English | — | 1269 |
| LMArena Chinese | — | 1320 |
| LMArena French | — | 1305 |
| LMArena German | — | 1267 |
| LMArena Japanese | — | 1228 |
| LMArena Korean | — | 1192 |
| LMArena Russian | — | 1255 |
| LMArena Spanish | — | 1315 |
Instruction Following Not comparable
GPT-5.1-Codex: —, Yi-Lightning: 67.4 (#196)
| Benchmark | GPT-5.1-Codex | Yi-Lightning |
|---|---|---|
| LMArena Instruction Following | — | 1278 |
Long Context Not comparable
GPT-5.1-Codex: —, Yi-Lightning: 39.4 (#181)
| Benchmark | GPT-5.1-Codex | Yi-Lightning |
|---|---|---|
| LMArena Longer Query | — | 1297 |
Writing & Preference Not comparable
GPT-5.1-Codex: —, Yi-Lightning: 50.2 (#184)
| Benchmark | GPT-5.1-Codex | Yi-Lightning |
|---|---|---|
| LMArena Text | — | 1302 |
| LMArena Creative Writing | — | 1280 |
| LMArena Multi-Turn | — | 1311 |
Frequently asked questions
Is GPT-5.1-Codex better than Yi-Lightning?
GPT-5.1-Codex is the stronger model overall, scoring 38.6 to 37.1 on the Noometry Index.
Is GPT-5.1-Codex or Yi-Lightning better for coding?
GPT-5.1-Codex scores higher on coding benchmarks: 41.9 versus 27.4 in the Noometry coding category.
How many benchmarks do GPT-5.1-Codex and Yi-Lightning share?
0 benchmarks have published results for both models. GPT-5.1-Codex has 6 scored results on Noometry and Yi-Lightning has 18.