Cheaper overall
Claude Sonnet 5.5
50% lower blended rate
Higher benchmark scores
Claude Opus 5.5
leads on 13 of 14 figures
Cheaper cached input
Claude Sonnet 5.5
$0.10 vs $0.20, 50% less
Where each one wins
Claude Sonnet 5.5
- Cheaper input tokens $2.00 vs $4.00, 50% less
- Cheaper output tokens $10.00 vs $20.00, 50% less
- Cheaper cached input $0.10 vs $0.20, 50% less
- Cheaper on all four workloads
- Higher answer reliability (Omniscience Non-Hallucination) 53 vs 41.4
Claude Opus 5.5
- Higher overall intelligence (Intelligence Index) 57.6 vs 56
- Higher expert-exam performance (Humanity's Last Exam) 61.4 vs 55
- Higher long-context reasoning (AA-LCR) 84.7 vs 82.7
- Ahead on 10 more benchmark figures
What four workloads cost
One run, and the same run a thousand times.
Claude Sonnet 5.5 is cheaper on all four workloads, by much the same margin each time — about 2 times, from $0.0070 against $0.0140 on a chat turn to $0.8300 against $1.66 on a long document.
| Workload | Claude Sonnet 5.5 | Claude Opus 5.5 | ×1,000 | Difference |
|---|---|---|---|---|
| Chat turn 1,000 in / 500 out | $0.0070 | $0.0140 | $7.00 / $14.00 | Claude Sonnet 5.5 is 50% cheaper |
| RAG answer 10,000 in / 800 out | $0.0280 | $0.0560 | $28.00 / $56.00 | Claude Sonnet 5.5 is 50% cheaper |
| Agent loop 32,000 in / 700 out × 20 calls | $0.2800 | $0.5600 | $280.00 / $560.00 | Claude Sonnet 5.5 is 50% cheaper |
| Long document 400,000 in / 3,000 out | $0.8300 | $1.66 | $830.00 / $1,660.00 | Claude Sonnet 5.5 is 50% cheaper |
Price per 1M tokens
Neither model changes its rate with prompt length, so these rates apply to every request.
| Context band | Price | Claude Sonnet 5.5 | Claude Opus 5.5 | Difference |
|---|---|---|---|---|
| Any prompt length | Input | $2.00 | $4.00 | Claude Sonnet 5.5 is 50% cheaper |
| Any prompt length | Cached input | $0.10 | $0.20 | Claude Sonnet 5.5 is 50% cheaper |
| Any prompt length | Output | $10.00 | $20.00 | Claude Sonnet 5.5 is 50% cheaper |
Blended: Claude Sonnet 5.5 $4.00, Claude Opus 5.5 $8.00 per 1M — one rate at 3:1 input to output, for comparing two models at a glance.
Both priced by Anthropic. Standard tier, pay-as-you-go.
Other pricing tiers
Both models offer Batch, worth up to 50% off their standard rates, and the cheaper model is the same one on every tier — so the tier you buy changes the bill rather than the choice.
Every tier either model sells is here, so this is the whole price sheet. A saving is measured against that model's own standard rate — how we read tiers.
| Tier | Claude Sonnet 5.5 | Claude Opus 5.5 | Cheaper |
|---|---|---|---|
| Batch | $1.00 in / $5.00 out 50% off Standard | $2.00 in / $10.00 out 50% off Standard | Claude Sonnet 5.5 |
Benchmarks
They share 14 figures: Claude Sonnet 5.5 leads on 1, Claude Opus 5.5 on 13. The widest gap is 26 points, on Codecategories Elo.
Overall intelligence
Intelligence Index — Overall intelligence across reasoning, knowledge & math evals
Claude Opus 5.5 ahead by 1.6
Expert-exam performance
Humanity's Last Exam — Expert-level questions across many academic domains
Claude Opus 5.5 ahead by 6.4
Long-context reasoning
AA-LCR — Long-context reasoning across large inputs
Claude Opus 5.5 ahead by 2
Scientific coding
SciCode — Research-level scientific coding tasks
Claude Opus 5.5 ahead by 5.9
Physics research reasoning
CritPt — Unpublished physics research reasoning problems
Claude Opus 5.5 ahead by 0.3
Real-world task performance
GDPval — Economically valuable, real-world knowledge work
Claude Opus 5.5 ahead by 1.4
Factual accuracy
Omniscience Accuracy — Breadth of factual knowledge across domains
Claude Opus 5.5 ahead by 12.3
Answer reliability
Omniscience Non-Hallucination — How reliably the model avoids fabricated answers
Claude Sonnet 5.5 ahead by 11.6
3d Elo
Design Arena head-to-head rating in the 3d category
Claude Opus 5.5 ahead by 2
Codecategories Elo
Design Arena head-to-head rating in the codecategories category
Claude Opus 5.5 ahead by 26
Dataviz Elo
Design Arena head-to-head rating in the dataviz category
Claude Opus 5.5 ahead by 17
Gamedev Elo
Design Arena head-to-head rating in the gamedev category
Claude Opus 5.5 ahead by 5
Uicomponent Elo
Design Arena head-to-head rating in the uicomponent category
Claude Opus 5.5 ahead by 5
Website Elo
Design Arena head-to-head rating in the website category
Claude Opus 5.5 ahead by 3
Each figure is that model's best published run, with the effort level named beside it — where these scores come from.
Specifications
Only Claude Opus 5.5 lists code execution and computer use.
| Specification | Claude Sonnet 5.5 | Claude Opus 5.5 |
|---|---|---|
| Context window | 1,000,000 tokens | 1,000,000 tokens |
| Max output | 128,000 tokens | 128,000 tokens |
| Takes in | Text, image, file | Text, image, file |
| Puts out | Text | Text |
| Knowledge cutoff | — | 30 Jun 2026 |
| Released | 28 Sep 2026 | 22 Sep 2026 |
| Status | Active | Active |
| Sold by | Anthropic, Perplexity | Anthropic, Perplexity |
| Tool use | Yes | Yes |
| Structured outputs | Yes | Yes |
| Web search | Not listed | Not listed |
| Prompt caching | Yes | Yes |
| Code execution | Not listed | Yes |
| Computer use | Not listed | Yes |
| Open weights | Not listed | Not listed |
| Reasoning | Yes | Yes |
FAQs
- Is Claude Sonnet 5.5 cheaper than Claude Opus 5.5?
- Yes. A 1,000-token prompt with a 500-token reply costs $0.0070 on Claude Sonnet 5.5 and $0.0140 on Claude Opus 5.5, and the same model is cheaper on every workload on this page.
- How much do Claude Sonnet 5.5 and Claude Opus 5.5 cost per 1M tokens?
- Claude Sonnet 5.5 costs $2.00 for input and $10.00 for output. Claude Opus 5.5 costs $4.00 and $20.00. Standard pay-as-you-go rates, as of 8 Oct 2026.
- Which is better, Claude Sonnet 5.5 or Claude Opus 5.5?
- On published benchmarks, Claude Opus 5.5. It leads on 13 of the 14 figures both models report, including overall intelligence (Intelligence Index), where it scores 57.6 against 56.
- Is Batch pricing cheaper for Claude Sonnet 5.5 or Claude Opus 5.5?
- Batch input costs $1.00 on Claude Sonnet 5.5 and $2.00 on Claude Opus 5.5, 50% below the standard rate on both.