Model comparison
Claude Opus 5.5 vs Grok Build 0.1
Claude Opus 5.5 is the stronger model overall, scoring 68.6 to 36.4 on the Noometry Index. Grok Build 0.1 costs 6.4× less per token, which makes it the better buy when Claude Opus 5.5's lead doesn't matter for your workload.
Last verified . 2 shared benchmarks.
Summary
- They share 2 benchmarks with published results for both. Claude Opus 5.5 scores higher in 3 categories and Grok Build 0.1 in 0 categories; 3 gaps are clear of the uncertainty.
- The widest gap is in reasoning, where Claude Opus 5.5 leads 80.2 to 32.2.
- The biggest single-benchmark swing is CritPt: 31.7% for Claude Opus 5.5 and 9.1% for Grok Build 0.1.
- Grok Build 0.1 is cheaper at $1 / $2 per million input/output tokens, against $4 / $20 for Claude Opus 5.5.
- Claude Opus 5.5 accepts more context: 1M tokens versus 256K.
Side by side
| Claude Opus 5.5 | Grok Build 0.1 | |
|---|---|---|
| Provider | Anthropic | xAI |
| Noometry Index | 68.6 | 36.4 |
| Released | 2026-09-22 | 2026-04-16 |
| Weights | Proprietary | Proprietary |
| Context window | 1M | 256K |
| Max output | 128K | 256K |
| Input $ / M tokens | $4 | $1 |
| Output $ / M tokens | $20 | $2 |
| Results tracked | 44 | 3 |
Sponsored placements are available on pages like this one. Advertise on Noometry
Category by category
Coding Claude Opus 5.5 leads
Claude Opus 5.5: 71.9 (#3), Grok Build 0.1: 43.1 (#91)
| Benchmark | Claude Opus 5.5 | Grok Build 0.1 |
|---|---|---|
| SciCode | 66.9% | 50.2% |
| FrontierCode | 54.6% | — |
| CursorBench | 57.8% | — |
| LMArena WebDev | 1813 | — |
| FrontierSWE | 62.3% | — |
| LMArena Coding | 1547 | — |
| MirrorCode | 77.4% | — |
| ALE-Bench | 2,147 | — |
Agentic & Tool Use Claude Opus 5.5 leads
Claude Opus 5.5: 45.3 (#15), Grok Build 0.1: 22.7 (#129)
| Benchmark | Claude Opus 5.5 | Grok Build 0.1 |
|---|---|---|
| APEX-Agents | 73.5% | — |
| GBAEval | — | 2.4% |
| GDP.pdf | 30.6% | — |
| Vending-Bench 2 | 9,235 | — |
Reasoning Claude Opus 5.5 leads
Claude Opus 5.5: 80.2 (#3), Grok Build 0.1: 32.2 (#77)
| Benchmark | Claude Opus 5.5 | Grok Build 0.1 |
|---|---|---|
| CritPt | 31.7% | 9.1% |
| ARC-AGI-2 | 93.3% | — |
| NYT Connections (extended) | 88.5% | — |
| ARC-AGI-1 | 98.5% | — |
| EBR-Bench | 71.4% | — |
| LMArena Hard Prompts | 1535 | — |
| Mystery Game Puzzles | 71% | — |
| DTBench | 98.9% | — |
| LMCA | 68.2% | — |
| Epoch Capabilities Index | 167.33 | — |
Math Not comparable
Claude Opus 5.5: 91.8 (#3), Grok Build 0.1: —
| Benchmark | Claude Opus 5.5 | Grok Build 0.1 |
|---|---|---|
| FrontierMath (Tiers 1-3) | 91.2% | — |
| FrontierMath Tier 4 | 95% | — |
| OTIS Mock AIME 2024-2025 | 100% | — |
| ProofBench | 100% | — |
| LMArena Math | 1506 | — |
| FrontierMath Erdős | 2.9% | — |
Knowledge Not comparable
Claude Opus 5.5: 66.4 (#10), Grok Build 0.1: —
| Benchmark | Claude Opus 5.5 | Grok Build 0.1 |
|---|---|---|
| GPQA Diamond | 90.6% | — |
| SimpleQA Verified | 72.2% | — |
| LMArena Expert | 1547 | — |
Multimodal Not comparable
Claude Opus 5.5: 57.8 (#1), Grok Build 0.1: —
| Benchmark | Claude Opus 5.5 | Grok Build 0.1 |
|---|---|---|
| LMArena Vision | 1321 | — |
| Blueprint-Bench 2 | 51.2% | — |
| Furniture Assembly | 83.3% | — |
Multilingual Not comparable
Claude Opus 5.5: 59.1 (#2), Grok Build 0.1: —
| Benchmark | Claude Opus 5.5 | Grok Build 0.1 |
|---|---|---|
| LMArena Non-English | 1507 | — |
| LMArena Chinese | 1588 | — |
| LMArena French | 1514 | — |
| LMArena Russian | 1520 | — |
| LMArena Spanish | 1507 | — |
Instruction Following Not comparable
Claude Opus 5.5: 80.0 (#3), Grok Build 0.1: —
| Benchmark | Claude Opus 5.5 | Grok Build 0.1 |
|---|---|---|
| LMArena Instruction Following | 1537 | — |
Long Context Not comparable
Claude Opus 5.5: 47.1 (#19), Grok Build 0.1: —
| Benchmark | Claude Opus 5.5 | Grok Build 0.1 |
|---|---|---|
| LMArena Longer Query | 1532 | — |
Writing & Preference Not comparable
Claude Opus 5.5: 78.2 (#3), Grok Build 0.1: —
| Benchmark | Claude Opus 5.5 | Grok Build 0.1 |
|---|---|---|
| LMArena Text | 1515 | — |
| LMArena Creative Writing | 1533 | — |
| EQ-Bench Creative Writing | 2050 | — |
| LMArena Multi-Turn | 1499 | — |
Frequently asked questions
Is Claude Opus 5.5 better than Grok Build 0.1?
Claude Opus 5.5 is the stronger model overall, scoring 68.6 to 36.4 on the Noometry Index. Grok Build 0.1 costs 6.4× less per token, which makes it the better buy when Claude Opus 5.5's lead doesn't matter for your workload.
Which is cheaper, Claude Opus 5.5 or Grok Build 0.1?
Grok Build 0.1 is cheaper. It lists at $1 per million input tokens and $2 per million output tokens; Claude Opus 5.5 lists at $4 and $20.
Is Claude Opus 5.5 or Grok Build 0.1 better for coding?
Claude Opus 5.5 scores higher on coding benchmarks: 71.9 versus 43.1 in the Noometry coding category.
Which has the bigger context window?
Claude Opus 5.5 does, with 1M tokens against 256K.
How many benchmarks do Claude Opus 5.5 and Grok Build 0.1 share?
2 benchmarks have published results for both models. Claude Opus 5.5 has 44 scored results on Noometry and Grok Build 0.1 has 3.