Claude Opus 5.5
Pricing & Specs

Anthropic · $4 input / $20 output per 1M tokens · 1M context window

$4
per 1M input tokens
$20
per 1M output tokens
1M
context window (tokens)

The per-token price never tells the full story. A typical task (1K input + 500 output tokens) on Claude Opus 5.5 costs about $0.0140, roughly $14.00 per 1,000 runs. But if it needs 3x the tokens of a cheaper model to match quality on YOUR task, the economics flip. The only way to know is to benchmark it on your actual workload.

Claude Opus 5.5 API Pricing

TokensPrice
Input$4 / 1M tokens
Output$20 / 1M tokens
Cached input$0.2 / 1M tokens

50% discount available for batch API requests. Cache writes: $5/MTok (5min), $8/MTok (1hr). Cache reads: $0.20/MTok (5% of input). Min cacheable prompt 512 tokens. Fast mode available (research preview), priced separately.

What that means in practice

1x One typical task (1K input + 500 output tokens): $0.0140
1K 1,000 runs of that task: $14.00
💡 Real cost depends on how verbose the model is on YOUR prompts. Benchmark to measure actual tokens, not estimates.

Claude Opus 5.5 Specs

SpecValue
Context window1M tokens
Max output tokens128K tokens
Input modalitiestext, image
Output modalitiestext
Knowledge cutoffJun 2026
Reasoning modelYes
Tool / function callingYes
JSON modeYes
StreamingYes
Prompt cachingYes
Batch APIYes

Notes

Released September 22, 2026. Adaptive thinking always on (cannot be disabled), default effort medium. Breaking vs Opus 5: forced tool use returns error; thinking blocks tied to producing model; text between tool calls returned in thinking blocks (empty at default display).

FAQ

How much does Claude Opus 5.5 cost?

Claude Opus 5.5 costs $4 per 1M input tokens and $20 per 1M output tokens ($0.2 per 1M cached input tokens).

What is Claude Opus 5.5's context window?

Claude Opus 5.5 has a 1M-token context window. Maximum output is 128K tokens.

Can I test Claude Opus 5.5 on my own task?

Yes. OpenMark lets you benchmark Claude Opus 5.5 against 100+ models on your own task with real API calls, with no API keys needed, free tier available.

Is Claude Opus 5.5 the right model for YOUR task?

Pricing tables can't answer that. Benchmark it against 100+ models
on your actual workload: real API calls, real costs. Free tier available.

Benchmark Claude Opus 5.5 Free →

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