// Anthropic
Claude Sonnet 5.5
A Anthropic model. 1 prices across 1 channels side by side, each with its source and check date – plus specs, licence, speed and benchmarks.
- Official in/out per 1M
- $2 / $10
- Lowest (official)
- $2 / $10
- Context
- 1M
- AA index
- 56
Prices checked 2026-10-10Official sources linked on every rowNo estimatesCheapest LLM APIs →
01Specs at a glance
Official values first; gaps filled from OpenRouter’s API where the vendor page is silent.
| Vendor | Anthropic |
|---|---|
| Context window | 1M (1,000,000 tokens) |
| Max output | 128K |
| Input | Text · Image |
| Output | Text |
| Tool calling / JSON | Yes / Yes |
| Weights & licence | Closed · Proprietary (API only) |
| Released | Sep 28, 2026 (OpenRouter listing date) |
| Model IDs | claude-sonnet-5-5 |
02Prices on 1 channels
Per 1M tokens, in the currency each source publishes (1 USD = 6.7 CNY for the blended column). Sorted: official first, then cheapest.
| Channel | Source | Input | Output | Cache hit | Blended $ | Context | Notes |
|---|---|---|---|---|---|---|---|
| Official Vendor API, billed in USD | Official 10-10 | $2 | $10 | $0.1 | 4 | 1M | Batch −50%Batch -50%; cache write 5m=1.25x input, 1h=2x input; 1M ctx / 128K out |
“Official” = vendor pricing page; “Platform” = the platform’s own pricing page; “OpenRouter” = price listed on OpenRouter, not checked on the platform’s site. Click a source tag to open the original page.
03Where you can use it
Derived only from the price sources above. Country restrictions are set by each vendor – check their terms before you sign up.
- Vendor API, billed in USD
Official
04Performance
All results →Speed and AA index from Artificial Analysis public leaderboards (not our own tests); benchmark scores from our benchmark library, best result per benchmark.
- AA indexClaude Sonnet 5.5 (Max, Default Fallback)
- 56
- Output speed (median)
- 134 tok/s
- Time to first tokenClaude Sonnet 5.5 (Low, Default Fallback): 1.23s
- 418s
- AA index per $ (blended)
- 14
Default TTFT includes thinking time at the highest reasoning setting; low-effort settings respond much faster.
| Benchmark | Best score | Source | Date |
|---|---|---|---|
| LMArena Text | 1476 | official | 2026-10-08 |
| LMArena WebDev | 1774 | official | 2026-10-08 |
| LMArena Vision | 1268 | official | 2026-10-02 |
| GPQA Diamond | 95.6% | independent | 2026-09-29 |
| AIME (OTIS Mock AIME 2024–2025) | 100.0% | independent | 2026-09-29 |
| Humanity's Last Exam | 46.1% | compiled | 2026-09-28 |
05Price changes we recorded
All price changes →From our daily re-checks of the sources above.
No price change recorded since we started tracking (2026-10-10).
06More from Anthropic
FAQ
How much does the Claude Sonnet 5.5 API cost?
On the official pricing page: $2 / $10 per 1M input / output tokens, cached input $0.1 (checked 2026-10-10).
What is the context window of Claude Sonnet 5.5?
1M tokens of context, up to 128K output tokens. Platforms may cap it lower – see the table.
Is Claude Sonnet 5.5 open source?
No. It is only available through APIs and the vendor’s apps.