Compare / Claude Opus 5.5 vs Gemini 4 Argon
Claude Opus 5.5 vs Gemini 4 Argon
Which is cheaper, which is more capable, and which does better at each kind of work, from 16 results on 2 sources that measured both models.
Results as of 8 October 2026 (catalogue release 2026-10-08-4199ce0620fe).
Claude Opus 5.5 or Gemini 4 Argon? The short answer
Pick Claude Opus 5.5: it scores higher (Intelligence Index 57.6 against 52.6) at about the same price.
- Claude Opus 5.5 scores higher on the Artificial Analysis Intelligence Index: 57.6 against 52.6.
- Gemini 4 Argon is newer: released 30 Sep 2026, against 22 Sep 2026 for Claude Opus 5.5.
- On third-party benchmarks, on the results both models have: Claude Opus 5.5 does better for agents and tool use and reasoning and knowledge; Gemini 4 Argon for writing.
At a glance
| Claude Opus 5.5 | Gemini 4 Argon | |
|---|---|---|
| Price per million tokens | $4.00 in · $20.00 out | Not on sale |
| Blended (3 in : 1 out) | $8.00 | – |
| Cheapest host, blended | $8.00 (Amazon Bedrock) | – |
| Cached input, per million | $0.20 cached input | – |
| Intelligence Index | 57.6 | 52.6 |
| Spring Prompt overall | 85 | – |
| Output speed, tokens a second | 97 | – |
| Context window | 1,000,000 tokens | – |
| Released | 22 Sep 2026 | 30 Sep 2026 (newer) |
| Weights | Closed | Closed |
| Developer based in | the US | the US |
Prices are the developer's list price where we have read it, otherwise the typical host on OpenRouter; see every model's price. Intelligence and speed from Artificial Analysis.
Which is better for what
Each model's rank among models available today, for each kind of work, from our own benchmarks and licensed sources. The better rank is in green.
| Use case | Claude Opus 5.5 | Gemini 4 Argon |
|---|---|---|
| Product listingsTurning a sparse product feed and photos into listings that can go live | 6 of 20 | not measured |
| Decks from an analysisTurning a finished analysis into a deck you could present as it is | 5 of 19 | not measured |
| User surveysPlanning a user survey and reading its results without being misled | 2 of 8 | not measured |
| Marketing planningPlanning a year of ad spend without overspending | 5 of 19 | not measured |
| Agents and tool useMulti-step tasks with tools: support desks, coding agents, function calls | 2 of 164 | 3 of 165 |
| Professional workReal tasks from banking, consulting and law, business documents and freelance projects | 3 of 51 | not measured |
| Reasoning and knowledgeHard questions across science, maths and general knowledge | 1 of 198 | 3 of 199 |
| WritingWhat people prefer in blind comparisons, and judged writing quality | 4 of 188 | 1 of 189 |
| Sticking to the factsSummarising without inventing things, and factual answers | 2 of 152 | 1 of 153 |
| Speed under pressureGood decisions against a real clock (fast chess) | 23 of 23 | not measured |
Every shared result
Each model's best result on every measure both have, grouped by benchmark, with the setting that produced it. The headline measures of each benchmark come first; the rest are under "Show all". Green marks the better value; where a source reports ranges that overlap, neither is marked.
| Measure | Claude Opus 5.5 | Gemini 4 Argon |
|---|---|---|
| Arena (formerly LMArena) reported by Arena (formerly LMArena) · 3 results | ||
| Overall · TextArena rating, higher is better | 1,504high reasoning | 1,525high reasoning |
| Overall · Text factualityArena rating, higher is better | 1,507high reasoning | 1,511high reasoning |
| Business, management and finance · TextArena rating, higher is better | 1,489high reasoning | 1,522high reasoning |
| Artificial Analysis reported by Artificial Analysis · 3 results | ||
| Artificial Analysis Intelligence Indexindex score, higher is better | 57.6max reasoning | 52.6high reasoning |
| Humanity's Last Exam% of questions, higher is better | 61.4%max reasoning | 57.1%high reasoning |
| Terminal-Bench 4.0% of tasks, higher is better | 59.6%max reasoning | 57.1%high reasoning |
Show all 16 results (10 more)
| Measure | Claude Opus 5.5 | Gemini 4 Argon |
|---|---|---|
| Arena (formerly LMArena) reported by Arena (formerly LMArena) · 8 results | ||
| Confirmed task success · AgentIPS effect estimate, higher is better | 0.14high reasoning, arena agent | 0.15high reasoning, arena agent |
| Creative writing · TextArena rating, higher is better | 1,516high reasoning | 1,519high reasoning |
| Expert prompts · TextArena rating, higher is better | 1,541high reasoning | 1,539high reasoning |
| Instruction following · TextArena rating, higher is better | 1,517high reasoning | 1,528high reasoning |
| Praise over complaint · AgentIPS effect estimate, higher is better | 0.31high reasoning, arena agent | 0.28high reasoning, arena agent |
| Steerability · AgentIPS effect estimate, higher is better | 0.10high reasoning, arena agent | 0.13high reasoning, arena agent |
| Tool grounding · AgentIPS effect estimate, higher is better | 0.00high reasoning, arena agent | 0.00high reasoning, arena agent |
| Writing, literature and language · TextArena rating, higher is better | 1,519high reasoning | 1,522high reasoning |
| Artificial Analysis reported by Artificial Analysis · 2 results | ||
| Long-context reasoning (AA-LCR)% of questions, higher is better | 84.7%max reasoning | 79.7%high reasoning |
| SciCode% of problems, higher is better | 66.9%max reasoning | 61.8%high reasoning |
Quick answers
Is Claude Opus 5.5 better than Gemini 4 Argon?
Pick Claude Opus 5.5: it scores higher (Intelligence Index 57.6 against 52.6) at about the same price.
Run Claude Opus 5.5 and Gemini 4 Argon on your own prompt
Benchmarks aren't your data. Try both side by side in the playground, with the cost of every answer.