Model comparison
Claude 2.1 vs GPT-5.1-Codex
GPT-5.1-Codex is the stronger model overall, scoring 38.6 to 25.2 on the Noometry Index.
Last verified . 0 shared benchmarks.
Summary
- The widest gap is in math, where GPT-5.1-Codex leads 30.3 to 10.2.
Side by side
| Claude 2.1 | GPT-5.1-Codex | |
|---|---|---|
| Provider | Anthropic | OpenAI |
| Noometry Index | 25.2 | 38.6 |
| Released | 2023-11-21 | 2025-11-12 |
| Weights | Proprietary | Proprietary |
| Context window | — | 400K |
| Max output | — | 128K |
| Input $ / M tokens | — | $1.25 |
| Output $ / M tokens | — | $10 |
| Results tracked | 7 | 6 |
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Category by category
Coding GPT-5.1-Codex leads
Claude 2.1: 26.2 (#327), GPT-5.1-Codex: 41.9 (#116)
| Benchmark | Claude 2.1 | GPT-5.1-Codex |
|---|---|---|
| SWE-bench Verified (bash only) | — | 66% |
| LMArena WebDev | — | 1337 |
| WeirdML | 7.1% | — |
| ALE-Bench | — | 1,245 |
Agentic & Tool Use Not comparable
Claude 2.1: —, GPT-5.1-Codex: 38.0 (#33)
| Benchmark | Claude 2.1 | GPT-5.1-Codex |
|---|---|---|
| Terminal-Bench | — | 60.4% |
| METR Time Horizons | — | 70.8% |
Reasoning Not comparable
Claude 2.1: 21.4 (#221), GPT-5.1-Codex: —
| Benchmark | Claude 2.1 | GPT-5.1-Codex |
|---|---|---|
| DTBench | 51% | — |
| Epoch Capabilities Index | 119.27 | — |
| ForecastBench | 54.2 | — |
Math GPT-5.1-Codex leads
Claude 2.1: 10.2 (#315), GPT-5.1-Codex: 30.3 (#235)
| Benchmark | Claude 2.1 | GPT-5.1-Codex |
|---|---|---|
| OTIS Mock AIME 2024-2025 | 1.9% | — |
| ProofBench | — | 9% |
Knowledge Not comparable
Claude 2.1: 15.4 (#292), GPT-5.1-Codex: —
| Benchmark | Claude 2.1 | GPT-5.1-Codex |
|---|---|---|
| GPQA Diamond | 33% | — |
| MMLU | 73.5% | — |
Frequently asked questions
Is Claude 2.1 better than GPT-5.1-Codex?
GPT-5.1-Codex is the stronger model overall, scoring 38.6 to 25.2 on the Noometry Index.
Is Claude 2.1 or GPT-5.1-Codex better for coding?
GPT-5.1-Codex scores higher on coding benchmarks: 41.9 versus 26.2 in the Noometry coding category.
How many benchmarks do Claude 2.1 and GPT-5.1-Codex share?
0 benchmarks have published results for both models. Claude 2.1 has 7 scored results on Noometry and GPT-5.1-Codex has 6.