Claude Opus 5.5 vs Gemini 4 Argon
Official Anthropic and Google API prices and LMArena scores, checked 2026-10-18. Add up to 2 more models to compare 4.
Gemini 4 Argon costs less; LMArena tasks are split evenly.
Gemini 4 Argon is 2x cheaper on input and output. Gemini 4 Argon scores 66 points higher for roleplay; Claude Opus 5.5 scores 45 points higher for coding. Across 6 shared LMArena tasks, they split 3 to 3. A medium month (20M input + 5M output tokens) costs $180 on Claude Opus 5.5 and $90 on Gemini 4 Argon.
- Pick Claude Opus 5.5 if you care most about coding (+45), agent tasks (+17) and creative writing (+5).
- Pick Gemini 4 Argon if you want the lower bill ($90 vs $180 for a medium month), you care most about roleplay (+66), reasoning and math (+47) and chat (+28) or you reuse long prompts (cached input $0.10 vs $0.20).
Medium: 20M input + 5M output tokens a month at list price (short-context rate, no caching or batch discounts).
Marked side is better: lower for prices, higher for context and scores. Bars are scaled to the larger of the two.
| Spec | Claude Opus 5.5 | Gemini 4 Argon |
|---|---|---|
| Price per 1M tokens | ||
| Input | $4 | $2 |
| Cached input | $0.20 | $0.10 |
| Output | $20 | $10 |
| Blend 3:1 | $8 | $4 |
| Sample month, medium | $180 | $90 |
| Context | ||
| Context window | 1M tokens | 1M tokens |
| Quality (LMArena, out of 100) | ||
| Coding | 100/100 #1 of 23 | 55/100 #8 of 23 |
| Chat | 72/100 #3 of 25 | 100/100 #1 of 25 |
| Creative writing | 100/100 #1 of 25 | 95/100 #2 of 25 |
| Roleplay and characters | 34/100 #4 of 25 | 100/100 #1 of 25 |
| Reasoning and math | 53/100 #6 of 24 | 100/100 #1 of 24 |
| Vision | 82/100 #3 of 21 | Not ranked |
| Long documents | Not ranked | Not ranked |
| Cheap bulk and agents | 100/100 #1 of 23 | 83/100 #5 of 23 |
| Details | ||
| Provider | Anthropic | |
| API model id | claude-opus-5.5 | gemini-4-argon |
| Notes | 5-minute cache writes $5. | Launch price through Nov 30, 2026. From Dec 1: $4 in, $20 out. |
| Sources | ||
| Last checked | 2026-10-18 | 2026-10-18 |
| Official pricing | Anthropic pricing | Google pricing |
Plans from data checked hourly against each vendor's official pricing page. Vendors state limits in different units, so we quote them as published. Team and enterprise plans are per seat.
API prices in USD per 1M tokens from each provider's official pricing page. Blend 3:1 = (3 x input + output) / 4. Sample month = stated input and output tokens at the list price, no caching. Quality: relative score out of 100 on each LMArena leaderboard (100 = top model we price on that board, n/a = not ranked there), data licensed CC BY 4.0. See how we pick.
Where each one ranks on LMArena
Relative score out of 100 on each leaderboard (100 = the top model we price there), with the rank among the models from our API price table that appear on that board.
- Coding (Code Arena): Claude Opus 5.5 #1 of 23 (100/100), Gemini 4 Argon #8 of 23 (55/100)
- Chat (Text Arena): Claude Opus 5.5 #3 of 25 (72/100), Gemini 4 Argon #1 of 25 (100/100)
- Creative writing (Text Arena creative writing): Claude Opus 5.5 #1 of 25 (100/100), Gemini 4 Argon #2 of 25 (95/100)
- Roleplay and characters (Text Arena multi-turn): Claude Opus 5.5 #4 of 25 (34/100), Gemini 4 Argon #1 of 25 (100/100)
- Reasoning and math (Text Arena math): Claude Opus 5.5 #6 of 24 (53/100), Gemini 4 Argon #1 of 24 (100/100)
- Vision (Vision Arena): Claude Opus 5.5 #3 of 21 (82/100), Gemini 4 Argon not ranked
- Long documents (Document Arena): Claude Opus 5.5 not ranked, Gemini 4 Argon not ranked
- Cheap bulk and agents (Agent Arena): Claude Opus 5.5 #1 of 23 (100/100), Gemini 4 Argon #5 of 23 (83/100)
Pricing details from the official pages
Claude Opus 5.5 lists $4 input, $20 output, $0.20 cached input per 1M tokens on Anthropic pricing. Gemini 4 Argon lists $2 input, $10 output, $0.10 cached input per 1M tokens on Google pricing. Prices checked 2026-10-18.
- Claude Opus 5.5: 5-minute cache writes $5.
- Gemini 4 Argon: Launch price through Nov 30, 2026. From Dec 1: $4 in, $20 out.
Sample monthly bill at list price, no caching: Light (2M input + 0.5M output tokens): $18 vs $9. Medium (20M input + 5M output tokens): $180 vs $90. Heavy (200M input + 50M output tokens): $1,800 vs $900.
FAQ
Is Claude Opus 5.5 cheaper than Gemini 4 Argon?
Claude Opus 5.5 costs $4 input and $20 output per 1M tokens; Gemini 4 Argon costs $2 and $10. For a medium month (20M input + 5M output tokens) Gemini 4 Argon is cheaper: $90 vs $180.
Which is better for coding, Claude Opus 5.5 or Gemini 4 Argon?
On LMArena's Code Arena Claude Opus 5.5 scores 100/100 (#1 of 23) and Gemini 4 Argon 55/100 (#8 of 23), so Claude Opus 5.5 is ahead by 45 points.
Which has the bigger context window?
Claude Opus 5.5: 1M tokens. Gemini 4 Argon: 1M tokens. Both list the same window.
How much do Claude Opus 5.5 and Gemini 4 Argon cost per month?
Light (2M input + 0.5M output tokens): $18 vs $9. Medium (20M input + 5M output tokens): $180 vs $90. Heavy (200M input + 50M output tokens): $1,800 vs $900. Pick your own token counts in the plan vs API calculator.
Where do these numbers come from?
Prices come from each provider's official pricing page, checked daily. Quality is the relative score on the LMArena leaderboard dataset, licensed CC BY 4.0. Where a model is not ranked we show n/a.