# Claude Opus 4.8 vs Grok 4.20 Multi-Agent

> Claude Opus 4.8 is the stronger model overall, scoring 60.7 to 46.2 on the Noometry Index. Grok 4.20 Multi-Agent costs 6.4× less per token, which makes it the better buy when Claude Opus 4.8's lead doesn't matter for your workload.

- Canonical page: https://noometry.com/compare/claude-opus-4-8-vs-grok-4-20-multi-agent
- Last updated: 2026-10-12
- Shared benchmarks: 20

## Summary

- They share 20 benchmarks with published results for both. Claude Opus 4.8 scores higher in 9 categories and Grok 4.20 Multi-Agent in 0 categories; 8 gaps are clear of the uncertainty.
- The widest gap is in math, where Claude Opus 4.8 leads 78.4 to 39.4.
- Grok 4.20 Multi-Agent is cheaper at $1.25 / $2.50 per million input/output tokens, against $5 / $25 for Claude Opus 4.8.

## Snapshot

| | Claude Opus 4.8 | Grok 4.20 Multi-Agent |
|---|---|---|
| Provider | Anthropic | xAI |
| Noometry Index | 60.7 | 46.2 |
| Rank | 13 | 65 |
| Context | 1M | 1M |
| Input $/M | $5 | $1.25 |
| Output $/M | $25 | $2.50 |
| Weights | Proprietary | Proprietary |

## Coding

- Claude Opus 4.8: 59.9 (#12)
- Grok 4.20 Multi-Agent: 43.0 (#92)

| Benchmark | Claude Opus 4.8 | Grok 4.20 Multi-Agent |
|---|---|---|
| LMArena Coding | 1490 | 1457 |
| DeepSWE | 59% | — |
| FrontierCode | 46.5% | — |
| LMArena WebDev | 1556 | — |
| SciCode | 53.5% | — |
| GSO | 47.1% | — |
| WeirdML | 82.9% | — |
| ALE-Bench | 1,564 | — |

## Agentic & Tool Use

- Claude Opus 4.8: 47.6 (#11)
- Grok 4.20 Multi-Agent: —

| Benchmark | Claude Opus 4.8 | Grok 4.20 Multi-Agent |
|---|---|---|
| LMArena Search | 1204 | 1204 |
| APEX-Agents | 48.9% | — |
| OSWorld 2.0 | 20.6% | — |
| Remote Labor Index | 8.3% | — |
| τ²-bench Banking | 39.7% | — |
| DeepResearch Bench | 50.2% | — |
| PostTrainBench | 33.8% | — |
| GBAEval | 70.9% | — |
| GDP.pdf | 24% | — |
| Vending-Bench 2 | 5,787 | — |

## Reasoning

- Claude Opus 4.8: 64.7 (#16)
- Grok 4.20 Multi-Agent: 43.9 (#48)

| Benchmark | Claude Opus 4.8 | Grok 4.20 Multi-Agent |
|---|---|---|
| NYT Connections (extended) | 91.1% | 89.6% |
| LMArena Hard Prompts | 1482 | 1448 |
| ARC-AGI-2 | 72.1% | — |
| SimpleBench | 64.8% | — |
| Kagi LLM Benchmark | 88.8% | — |
| ARC-AGI-1 | 92.5% | — |
| CritPt | 20.9% | — |
| Chess Puzzles | 34% | — |
| EnigmaEval | 23.5% | — |
| EBR-Bench | 28.6% | — |
| Mystery Game Puzzles | 36% | — |
| DTBench | 94.9% | — |
| LMCA | 57.5% | — |
| Surface Evolver Bench | 87.5% | — |
| Bench to the Future 3 | 0.14 | — |
| Epoch Capabilities Index | 158.21 | — |
| ForecastBench | 59.9 | — |

## Math

- Claude Opus 4.8: 78.4 (#13)
- Grok 4.20 Multi-Agent: 39.4 (#104)

| Benchmark | Claude Opus 4.8 | Grok 4.20 Multi-Agent |
|---|---|---|
| LMArena Math | 1487 | 1442 |
| FrontierMath (Tiers 1-3) | 80% | — |
| FrontierMath Tier 4 | 56.1% | — |
| MathArena Final-Answer Competitions | 91.8% | — |
| OTIS Mock AIME 2024-2025 | 98.3% | — |
| ProofBench | 69% | — |
| FrontierMath (Feb 2025 set) | 47.2% | — |
| FrontierMath Tier 4 (v1) | 31.3% | — |

## Knowledge

- Claude Opus 4.8: 61.3 (#29)
- Grok 4.20 Multi-Agent: 40.4 (#119)

| Benchmark | Claude Opus 4.8 | Grok 4.20 Multi-Agent |
|---|---|---|
| LMArena Expert | 1502 | 1445 |
| GPQA Diamond | 91% | — |
| SimpleQA Verified | 53% | — |

## Multimodal

- Claude Opus 4.8: 42.9 (#26)
- Grok 4.20 Multi-Agent: 40.5 (#48)

| Benchmark | Claude Opus 4.8 | Grok 4.20 Multi-Agent |
|---|---|---|
| LMArena Vision | 1294 | 1259 |
| Blueprint-Bench 2 | 14.5% | — |
| Furniture Assembly | 42.5% | — |
| LMArena Document | 1475 | — |

## Multilingual

- Claude Opus 4.8: 55.2 (#33)
- Grok 4.20 Multi-Agent: 54.4 (#43)

| Benchmark | Claude Opus 4.8 | Grok 4.20 Multi-Agent |
|---|---|---|
| LMArena Non-English | 1450 | 1440 |
| LMArena Chinese | 1507 | 1475 |
| LMArena French | 1481 | 1466 |
| LMArena German | 1472 | 1456 |
| LMArena Japanese | 1440 | 1405 |
| LMArena Korean | 1432 | 1416 |
| LMArena Russian | 1474 | 1457 |
| LMArena Spanish | 1466 | 1447 |

## Instruction Following

- Claude Opus 4.8: 77.4 (#24)
- Grok 4.20 Multi-Agent: 74.8 (#84)

| Benchmark | Claude Opus 4.8 | Grok 4.20 Multi-Agent |
|---|---|---|
| LMArena Instruction Following | 1476 | 1420 |

## Long Context

- Claude Opus 4.8: 45.4 (#35)
- Grok 4.20 Multi-Agent: 43.7 (#88)

| Benchmark | Claude Opus 4.8 | Grok 4.20 Multi-Agent |
|---|---|---|
| LMArena Longer Query | 1483 | 1431 |

## Writing & Preference

- Claude Opus 4.8: 72.0 (#16)
- Grok 4.20 Multi-Agent: 64.0 (#59)

| Benchmark | Claude Opus 4.8 | Grok 4.20 Multi-Agent |
|---|---|---|
| LMArena Text | 1461 | 1450 |
| LMArena Creative Writing | 1454 | 1436 |
| LMArena Multi-Turn | 1476 | 1452 |
| EQ-Bench Creative Writing | 1840 | — |
| EQ-Bench 4 | 1281 | — |

## FAQ

### Is Claude Opus 4.8 better than Grok 4.20 Multi-Agent?

Claude Opus 4.8 is the stronger model overall, scoring 60.7 to 46.2 on the Noometry Index. Grok 4.20 Multi-Agent costs 6.4× less per token, which makes it the better buy when Claude Opus 4.8's lead doesn't matter for your workload.

### Which is cheaper, Claude Opus 4.8 or Grok 4.20 Multi-Agent?

Grok 4.20 Multi-Agent is cheaper. It lists at $1.25 per million input tokens and $2.50 per million output tokens; Claude Opus 4.8 lists at $5 and $25.

### Is Claude Opus 4.8 or Grok 4.20 Multi-Agent better for coding?

Claude Opus 4.8 scores higher on coding benchmarks: 59.9 versus 43.0 in the Noometry coding category.

### Which has the bigger context window?

Both accept 1M tokens.

### How many benchmarks do Claude Opus 4.8 and Grok 4.20 Multi-Agent share?

20 benchmarks have published results for both models. Claude Opus 4.8 has 65 scored results on Noometry and Grok 4.20 Multi-Agent has 20.