Claude Sonnet 4.5on Krater.ai
A major update to the Claude Sonnet line, offering near-Opus-level reasoning with significantly faster response times. Claude Sonnet 4.5 is the sweet spot of capability and speed.
Released September 29, 2025
Specifications
Claude Sonnet 4.5 at a glance
Context
1M tokens
Max output
64K tokens
Input
Text, Image, File
Output
Text
Input price
$3.00 / 1M
Output price
$15.00 / 1M
Knowledge cutoff
2025-01-31
Krater rank
#23
Capabilities
What it is good at
Catalog capabilities
- Accepts image input
- Generates text responses
- Supports tool calling
- Supports structured outputs
- Near-Opus reasoning at Sonnet speed
- Excellent coding and debugging
Good for
Benchmarks
Catalog data, not Krater benchmarks.
Coding index score
52.1
Agentic index score
26.4
Intelligence index score
37.4
Design Arena asciiart rank
#15
Design Arena mobileapps rank
#21
Compare
Compare Claude Sonnet 4.5
Claude Sonnet 4.5 vs Claude Sonnet 4
Claude Sonnet 4 significantly enhances the capabilities of its predecessor, Sonnet 3.7, excelling in both coding and reasoning tasks with improved precision and controllability.
Open comparisonClaude Sonnet 4.5 vs Claude Sonnet 4.6
Sonnet 4.6 is Anthropic's most capable Sonnet-class model yet, with frontier performance across coding, agents, and professional work.
Open comparisonClaude Sonnet 4.5 vs Claude Haiku 4.5
Claude Haiku 4.5 is Anthropic’s fastest and most efficient model, delivering near-frontier intelligence at a fraction of the cost and latency of larger Claude models.
Open comparisonFAQ
Questions about Claude Sonnet 4.5
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