Model comparison
Claude Opus 4.1 vs Molmo 2 8b
Claude Opus 4.1 is the stronger model overall, scoring 41.0 to 39.1 on the Noometry Index.
Last verified . 4 shared benchmarks.
Allen Institute for AI (Ai2)Summary
- They share 4 benchmarks with published results for both. Claude Opus 4.1 scores higher in 4 categories and Molmo 2 8b in 1 category; 5 gaps are clear of the uncertainty.
- The widest gap is in writing & preference, where Claude Opus 4.1 leads 62.4 to 49.4.
- Molmo 2 8b has downloadable open weights; the other is API-only.
Side by side
| Claude Opus 4.1 | Molmo 2 8b | |
|---|---|---|
| Provider | Anthropic | Allen Institute for AI (Ai2) |
| Noometry Index | 41.0 | 39.1 |
| Released | 2025-08-05 | — |
| Weights | Proprietary | Open |
| Context window | 200K | — |
| Max output | 32K | — |
| Input $ / M tokens | $15 | — |
| Output $ / M tokens | $75 | — |
| Results tracked | 48 | 5 |
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Category by category
Coding Not comparable
Claude Opus 4.1: 44.4 (#73), Molmo 2 8b: —
| Benchmark | Claude Opus 4.1 | Molmo 2 8b |
|---|---|---|
| SWE-bench Verified | 73.3% | — |
| LMArena WebDev | 1390 | — |
| WeirdML | 45.9% | — |
| LMArena Coding | 1479 | — |
| ALE-Bench | 674.77 | — |
| AlgoTune | 1.34 | — |
Agentic & Tool Use Not comparable
Claude Opus 4.1: 35.0 (#41), Molmo 2 8b: —
| Benchmark | Claude Opus 4.1 | Molmo 2 8b |
|---|---|---|
| Terminal-Bench | 38% | — |
| GDPval | 43.6% | — |
| Cybench | 42% | — |
| DeepResearch Bench | 48.3% | — |
| LMArena Search | 1148 | — |
| METR Time Horizons | 66.8% | — |
Reasoning Claude Opus 4.1 leads
Claude Opus 4.1: 32.2 (#76), Molmo 2 8b: 25.6 (#146)
| Benchmark | Claude Opus 4.1 | Molmo 2 8b |
|---|---|---|
| LMArena Hard Prompts | 1443 | 1287 |
| SimpleBench | 60% | — |
| Chess Puzzles | 7% | — |
| EnigmaEval | 7.2% | — |
| EBR-Bench | 7.9% | — |
| Mystery Game Puzzles | 21% | — |
| DTBench | 80% | — |
| LMCA | 37.1% | — |
| Epoch Capabilities Index | 144.12 | — |
| ForecastBench | 62 | — |
Math Not comparable
Claude Opus 4.1: 22.3 (#277), Molmo 2 8b: —
| Benchmark | Claude Opus 4.1 | Molmo 2 8b |
|---|---|---|
| FrontierMath (Tiers 1-3) | 12.6% | — |
| FrontierMath Tier 4 | 2.4% | — |
| OTIS Mock AIME 2024-2025 | 68.9% | — |
| LMArena Math | 1431 | — |
| FrontierMath (Feb 2025 set) | 7.2% | — |
| FrontierMath Tier 4 (v1) | 4.2% | — |
Knowledge Not comparable
Claude Opus 4.1: 42.0 (#101), Molmo 2 8b: —
| Benchmark | Claude Opus 4.1 | Molmo 2 8b |
|---|---|---|
| GPQA Diamond | 77.3% | — |
| Humanity's Last Exam | 11.5% | — |
| Confabulations | 17.1% | — |
| Vectara Hallucination Rate | 11.8% | — |
| LMArena Expert | 1439 | — |
Multimodal Molmo 2 8b leads
Claude Opus 4.1: 26.8 (#119), Molmo 2 8b: 30.2 (#112)
| Benchmark | Claude Opus 4.1 | Molmo 2 8b |
|---|---|---|
| LMArena Vision | — | 1081 |
| VPCT | 35% | — |
Multilingual Claude Opus 4.1 leads
Claude Opus 4.1: 52.0 (#95), Molmo 2 8b: 42.7 (#190)
| Benchmark | Claude Opus 4.1 | Molmo 2 8b |
|---|---|---|
| LMArena Non-English | 1405 | 1276 |
| LMArena Chinese | 1427 | — |
| LMArena French | 1431 | — |
| LMArena German | 1413 | — |
| LMArena Japanese | 1378 | — |
| LMArena Korean | 1380 | — |
| LMArena Russian | 1422 | — |
| LMArena Spanish | 1448 | — |
Instruction Following Claude Opus 4.1 leads
Claude Opus 4.1: 75.6 (#58), Molmo 2 8b: 67.0 (#201)
| Benchmark | Claude Opus 4.1 | Molmo 2 8b |
|---|---|---|
| LMArena Instruction Following | 1435 | 1270 |
Long Context Not comparable
Claude Opus 4.1: 44.5 (#63), Molmo 2 8b: —
| Benchmark | Claude Opus 4.1 | Molmo 2 8b |
|---|---|---|
| LMArena Longer Query | 1455 | — |
Writing & Preference Claude Opus 4.1 leads
Claude Opus 4.1: 62.4 (#74), Molmo 2 8b: 49.4 (#191)
| Benchmark | Claude Opus 4.1 | Molmo 2 8b |
|---|---|---|
| LMArena Text | 1419 | 1288 |
| LMArena Creative Writing | 1412 | — |
| Short-Story Creative Writing | 84.7% | — |
| LMArena Multi-Turn | 1444 | — |
Frequently asked questions
Is Claude Opus 4.1 better than Molmo 2 8b?
Claude Opus 4.1 is the stronger model overall, scoring 41.0 to 39.1 on the Noometry Index.
How many benchmarks do Claude Opus 4.1 and Molmo 2 8b share?
4 benchmarks have published results for both models. Claude Opus 4.1 has 48 scored results on Noometry and Molmo 2 8b has 5.