Model comparison
Claude Sonnet 5.5 vs Grok 4.20 Multi-Agent
Claude Sonnet 5.5 is the stronger model overall, scoring 60.5 to 45.5 on the Noometry Index. Grok 4.20 Multi-Agent costs 2.6× less per token, which makes it the better buy when Claude Sonnet 5.5's lead doesn't matter for your workload.
Last verified . 0 shared benchmarks.
Summary
- The widest gap is in math, where Claude Sonnet 5.5 leads 88.7 to 36.6.
- Grok 4.20 Multi-Agent is cheaper at $1.25 / $2.50 per million input/output tokens, against $2 / $10 for Claude Sonnet 5.5.
Side by side
| Claude Sonnet 5.5 | Grok 4.20 Multi-Agent | |
|---|---|---|
| Provider | Anthropic | xAI |
| Noometry Index | 60.5 | 45.5 |
| Released | 2026-09-28 | 2026-03-09 |
| Weights | Proprietary | Proprietary |
| Context window | 1M | 1M |
| Max output | 128K | 30K |
| Input $ / M tokens | $2 | $1.25 |
| Output $ / M tokens | $10 | $2.50 |
| Results tracked | 16 | 20 |
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Category by category
Coding Claude Sonnet 5.5 leads
Claude Sonnet 5.5: 65.5 (#6), Grok 4.20 Multi-Agent: 42.4 (#91)
| Benchmark | Claude Sonnet 5.5 | Grok 4.20 Multi-Agent |
|---|---|---|
| FrontierCode | 52.1% | — |
| CursorBench | 55.5% | — |
| LMArena WebDev | 1699 | — |
| FrontierSWE | 61.9% | — |
| SciCode | 61% | — |
| LMArena Coding | — | 1458 |
| ALE-Bench | 1,819 | — |
Agentic & Tool Use Not comparable
Claude Sonnet 5.5: 44.9 (#14), Grok 4.20 Multi-Agent: —
| Benchmark | Claude Sonnet 5.5 | Grok 4.20 Multi-Agent |
|---|---|---|
| APEX-Agents | 75.5% | — |
| LMArena Search | — | 1204 |
Reasoning Claude Sonnet 5.5 leads
Claude Sonnet 5.5: 52.4 (#29), Grok 4.20 Multi-Agent: 42.4 (#44)
| Benchmark | Claude Sonnet 5.5 | Grok 4.20 Multi-Agent |
|---|---|---|
| NYT Connections (extended) | — | 89.6% |
| CritPt | 31.4% | — |
| LMArena Hard Prompts | — | 1448 |
| Mystery Game Puzzles | 65% | — |
Math Claude Sonnet 5.5 leads
Claude Sonnet 5.5: 88.7 (#4), Grok 4.20 Multi-Agent: 36.6 (#106)
| Benchmark | Claude Sonnet 5.5 | Grok 4.20 Multi-Agent |
|---|---|---|
| FrontierMath (Tiers 1-3) | 88.8% | — |
| FrontierMath Tier 4 | 80.5% | — |
| OTIS Mock AIME 2024-2025 | 100% | — |
| ProofBench | 100% | — |
| LMArena Math | — | 1441 |
Knowledge Claude Sonnet 5.5 leads
Claude Sonnet 5.5: 66.0 (#11), Grok 4.20 Multi-Agent: 39.7 (#116)
| Benchmark | Claude Sonnet 5.5 | Grok 4.20 Multi-Agent |
|---|---|---|
| GPQA Diamond | 95.6% | — |
| SimpleQA Verified | 46.5% | — |
| LMArena Expert | — | 1445 |
Multimodal Claude Sonnet 5.5 leads
Claude Sonnet 5.5: 53.2 (#5), Grok 4.20 Multi-Agent: 39.8 (#44)
| Benchmark | Claude Sonnet 5.5 | Grok 4.20 Multi-Agent |
|---|---|---|
| LMArena Vision | — | 1259 |
| Furniture Assembly | 75% | — |
Multilingual Not comparable
Claude Sonnet 5.5: —, Grok 4.20 Multi-Agent: 54.6 (#40)
| Benchmark | Claude Sonnet 5.5 | Grok 4.20 Multi-Agent |
|---|---|---|
| LMArena Non-English | — | 1440 |
| LMArena Chinese | — | 1475 |
| LMArena French | — | 1467 |
| LMArena German | — | 1456 |
| LMArena Japanese | — | 1405 |
| LMArena Korean | — | 1416 |
| LMArena Russian | — | 1457 |
| LMArena Spanish | — | 1447 |
Instruction Following Not comparable
Claude Sonnet 5.5: —, Grok 4.20 Multi-Agent: 75.0 (#80)
| Benchmark | Claude Sonnet 5.5 | Grok 4.20 Multi-Agent |
|---|---|---|
| LMArena Instruction Following | — | 1420 |
Long Context Not comparable
Claude Sonnet 5.5: —, Grok 4.20 Multi-Agent: 43.7 (#84)
| Benchmark | Claude Sonnet 5.5 | Grok 4.20 Multi-Agent |
|---|---|---|
| LMArena Longer Query | — | 1430 |
Writing & Preference Not comparable
Claude Sonnet 5.5: —, Grok 4.20 Multi-Agent: 64.1 (#57)
| Benchmark | Claude Sonnet 5.5 | Grok 4.20 Multi-Agent |
|---|---|---|
| LMArena Text | — | 1450 |
| LMArena Creative Writing | — | 1435 |
| LMArena Multi-Turn | — | 1451 |
Frequently asked questions
Is Claude Sonnet 5.5 better than Grok 4.20 Multi-Agent?
Claude Sonnet 5.5 is the stronger model overall, scoring 60.5 to 45.5 on the Noometry Index. Grok 4.20 Multi-Agent costs 2.6× less per token, which makes it the better buy when Claude Sonnet 5.5's lead doesn't matter for your workload.
Which is cheaper, Claude Sonnet 5.5 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 Sonnet 5.5 lists at $2 and $10.
Is Claude Sonnet 5.5 or Grok 4.20 Multi-Agent better for coding?
Claude Sonnet 5.5 scores higher on coding benchmarks: 65.5 versus 42.4 in the Noometry coding category.
Which has the bigger context window?
Both accept 1M tokens.
How many benchmarks do Claude Sonnet 5.5 and Grok 4.20 Multi-Agent share?
0 benchmarks have published results for both models. Claude Sonnet 5.5 has 16 scored results on Noometry and Grok 4.20 Multi-Agent has 20.