Claude Opus 5.5 API pricing
Official Anthropic list price, last checked Oct 29, 2026. Updated Oct 29, 2026.
Claude Opus 5.5 costs $4 per 1M input tokens and $20 per 1M output tokens, cached input at $0.20, and a 1M-token context window, per Anthropic's official pricing page (checked Oct 29, 2026). It's a premium-priced model: number 71 of 77 by blended price ($8 per 1M tokens at a 3 to 1 input to output mix). On LMArena's Code Arena it ranks #1 of 50 models we price (relative score 100 out of 100). Nothing cheaper scores close to it on that board; Claude Sonnet 5.5 is the nearest cheaper option.
Claude Opus 5.5 price per million tokens
| Claude Opus 5.5 price per million tokens | USD |
|---|---|
| Input | $4 |
| Cached input | $0.20 |
| Output | $20 |
| Blended, 3 parts input to 1 part output | $8 |
| Context window | 1M tokens |
Official note from Anthropic: 5-minute cache writes $5.
What Claude Opus 5.5 costs for real work
List-price estimates for a month, no discounts. Our math, not a quote: change the token counts in the plan vs API calculator.
| Workload | Tokens a month | Claude Opus 5.5 | GPT-5.6 Sol | Claude Sonnet 5.5 |
|---|---|---|---|---|
| Light: a side project or personal assistant | 2M in, 0.5M out | $18.00 | $18.00 | $9.00 |
| Medium: a small team or one product feature | 20M in, 5M out | $180 | $180 | $90.00 |
| Heavy: a production app | 200M in, 50M out | $1,800 | $1,800 | $900 |
| Medium with 80% of input cached | 20M in (16M cached), 5M out | $119 | $122 | $59.60 |
How Claude Opus 5.5 ranks on LMArena
Relative score: 100 is the top model we price on that board. Rank is among the models in our price table, not the full leaderboard.
| Board | Rank | Score /100 |
|---|---|---|
| Coding (Code Arena) | #1 of 50 | 100 |
| Chat (Text Arena) | #2 of 51 | 78 |
| Creative writing (Text Arena creative writing) | #1 of 51 | 100 |
| Roleplay and characters (Text Arena multi-turn) | #5 of 51 | 37 |
| Reasoning and math (Text Arena math) | #5 of 51 | 64 |
| Vision (Vision Arena) | #3 of 33 | 84 |
| Cheap bulk and agents (Agent Arena) | #1 of 34 | 100 |
Closest rivals to Claude Opus 5.5
The models nearest in price, other makers first. Ranks are on Code Arena, where we have them.
| Model | In / out | Blended | Verdict |
|---|---|---|---|
| GPT-5.6 Sol | $4 / $20 | $8 | Same price, no score to separate them. Compare |
| Muse Wonder 1.0 | $4 / $20 | $8 | Claude Opus 5.5 wins: same price, higher score. Compare |
| Kimi K3.1 Pro Highspeed | $4 / $20 | $8 | Same price, no score to separate them. Compare |
| Kimi K3 | $3 / $15 | $6 | Kimi K3 for price, Claude Opus 5.5 for quality. Compare |
Cheaper alternatives to Claude Opus 5.5
At least 40% cheaper blended, best LMArena score first.
| Model | In / out | Blended | Verdict |
|---|---|---|---|
| Claude Sonnet 5.5 | $2 / $10 | $4 | Claude Sonnet 5.5 for price, Claude Opus 5.5 for quality. Compare |
| GPT-6.1 Sol | $2 / $10 | $4 | GPT-6.1 Sol for price, Claude Opus 5.5 for quality. Compare |
| Kimi K3.1 Pro | $2 / $10 | $4 | Kimi K3.1 Pro for price, Claude Opus 5.5 for quality. Compare |
More from Anthropic
- Claude Opus 5$5 in, $25 out per 1M
- Claude Sonnet 5.5$2 in, $10 out per 1M
- Claude Haiku 5.5$0.10 in, $0.50 out per 1M
- Claude Fable 5.1$10 in, $50 out per 1M
FAQ
How much does the Claude Opus 5.5 API cost per million tokens?
$4 per 1M input tokens and $20 per 1M output tokens, plus $0.20 per 1M for cached input, as of Oct 29, 2026. A typical 3 to 1 input to output mix works out to $8 per 1M tokens.
Does Claude Opus 5.5 charge more for long prompts?
Anthropic doesn't list a long-prompt surcharge for Claude Opus 5.5. Its pricing note says: 5-minute cache writes $5.
Is Claude Opus 5.5 cheaper than GPT-5.6 Sol?
About the same. A medium month (20M input and 5M output tokens) costs $180 on Claude Opus 5.5 and $180 on GPT-5.6 Sol at list price. On Code Arena, Claude Opus 5.5 ranks #1 and GPT-5.6 Sol isn't ranked.
How does Claude Opus 5.5 rank on LMArena?
On Code Arena it is #1 of 50 models we price, with a relative score of 100 out of 100. It ranks on 7 of 8 boards we track.
What is a cheaper alternative to Claude Opus 5.5?
Claude Sonnet 5.5 costs $2 in and $10 out per 1M tokens, about 2.0x less blended, and scores 85 on Code Arena against 100 for Claude Opus 5.5.
Where does this Claude Opus 5.5 price come from?
From Anthropic's official pricing page, which we check every day. This page was last checked Oct 29, 2026.