Compare

Claude Opus 5.5 vs Claude Sonnet 5

Pricing per million tokens, context window, capabilities — pulled from each provider's public docs. All 2 are available via the same AIgateway OpenAI-compatible endpoint; flip the model string to switch.

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Claude Opus 5.5
anthropic/claude-opus-5.5
Claude Sonnet 5
anthropic/claude-sonnet-5
Provider
Anthropic
Anthropic
Family
Claude 4
Claude 4
Modality
text
text
Context window
1,000,000 tok
1,000,000 tok
Max output
128,000 tok
128,000 tok
Released
2026-09-23
2026-07-07
License
Proprietary
Proprietary
Input price
$4.00 /1M
$2.00 /1M
Output price
$20.00 /1M
$10.00 /1M
Tools
yes
yes
Streaming
yes
yes
Vision
yes
yes
JSON mode
yes
yes
Reasoning
yes
yes
Prompt caching
Batch API
Try it
Open in playground →
Open in playground →
Claude Opus 5.5
anthropic/claude-opus-5.5
Full spec →

Claude Opus 5.5 is Anthropic's model for long-running agentic coding and knowledge work. It combines a one million token context window with adaptive thinking that is always on, a 128K token maximum output, and a medium default effort level.

Strengths
  • General-purpose chat
  • Long context
  • Tool use
Use cases
ChatbotsContent generationAgentic workflows
Claude Sonnet 5
anthropic/claude-sonnet-5
Full spec →

Claude Sonnet 5 is Anthropic's most agentic Sonnet model yet, built for coding, tool use, reasoning, and long-horizon professional work at lower cost than Opus-class models.

Strengths
  • General-purpose chat
  • Long context
  • Tool use
Use cases
ChatbotsContent generationAgentic workflows

Compare with another

Claude Opus 5.5 vs Grok 4.7
anthropic/claude-opus-5.5 · xai/grok-4.7
Claude Opus 5.5 vs GPT-6 Astra
anthropic/claude-opus-5.5 · openai/gpt-6-astra
Claude Opus 5.5 vs Claude Fable 5.1
anthropic/claude-opus-5.5 · anthropic/claude-fable-5.1
Claude Opus 5.5 vs Gemini 3.8 Flash
anthropic/claude-opus-5.5 · google/gemini-3.8-flash
Claude Opus 5.5 vs Glm-5.3
anthropic/claude-opus-5.5 · zai-org/glm-5.3
Claude Opus 5.5 vs Qwen3.8 Max
anthropic/claude-opus-5.5 · alibaba/qwen3.8-max
Claude Opus 5.5 vs Kimi K3
anthropic/claude-opus-5.5 · moonshot/kimi-k3
Claude Opus 5.5 vs Pareto
anthropic/claude-opus-5.5 · unbiased/pareto
Claude Opus 5.5 vs GPT-5.6 Sol
anthropic/claude-opus-5.5 · openai/gpt-5.6-sol
SWITCH BETWEEN THEM

One key, all 2, one line different.

from openai import OpenAI

client = OpenAI(
    base_url="https://api.aigateway.sh/v1",
    api_key="sk-aig-...",
)

# Claude Opus 5.5
client.chat.completions.create(
    model="anthropic/claude-opus-5.5",
    messages=[{"role":"user","content":"hello"}],
)

# Claude Sonnet 5
client.chat.completions.create(
    model="anthropic/claude-sonnet-5",
    messages=[{"role":"user","content":"hello"}],
)
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