Claude Sonnet 5.5
The balanced workhorse of the Claude 5 family, tuned for everyday production use where speed, quality and cost all matter. A default choice for chat, coding assistance and high-volume apps.
At a glance
Released
Sep 15, 2026
Provider
Anthropic
Context window
1,000,000 tokens
Max output
64,000 tokens
Modalities
Text + image → text
Knowledge cutoff
June 2026
API model ID
claude-sonnet-5-5License
Proprietary (API only)
Pricing
Standard
Input$2 / 1M
Output$10 / 1M
Batch (50% off)
Input$1 / 1M
Output$5 / 1M
A typical 1,500-token prompt with a 650-token answer costs ≈ $0.009 on the standard tier. Run your own prompt through the calculator →
What's new vs the previous model
Compared withClaude Sonnet 5 (April 2026)
- Faster responses at the same quality bar
- Improved coding and instruction following
- Better handling of mid-length context
- Not as deep on hard reasoning as Opus
Best use cases
Production chat
Handles high-volume assistant and support workloads cost-effectively.
Everyday coding
Writes, reviews and refactors code with quick turnaround.
Content generation
Drafts and edits text at scale with consistent quality.
Strengths & limitations
Strengths
- Strong price-performance balance
- Fast and capable
- Good coding ability
- Versatile
Limitations
- Less depth than Opus on hard problems
- Not the cheapest option
How to test it
- No-code: open claude.ai and pick Claude Sonnet 5.5 from the model switcher — no API key needed.
- Playground: sign in to the Anthropic Console and run prompts in the workbench, then copy the generated code.
- API: create a key in the Anthropic Console and call the API (example below).
curl https://api.anthropic.com/v1/messages \
-H "x-api-key: $ANTHROPIC_API_KEY" \
-H "anthropic-version: 2023-06-01" \
-H "content-type: application/json" \
-d '{
"model": "claude-sonnet-5-5",
"max_tokens": 1024,
"messages": [{"role": "user", "content": "Explain tokenization in one paragraph."}]
}'Where to get access
Consumer app
Chat with Claude Sonnet 5.5 in Claude apps (web, macOS, Windows, iOS, Android).
claude.ai ↗