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  1. Home
  2. /
  3. Compare

Claude Sonnet 5.5 vs Gemini 3.1 Pro Preview Custom Tools vs GPT-6 Astra

Compare Claude Sonnet 5.5 from Anthropic, Gemini 3.1 Pro Preview Custom Tools from Google, and GPT-6 Astra from OpenAI on key metrics including benchmarks, price, context length, and other model features. Access all 3 models and hundreds of others through the OpenRouter API.

Favicon for anthropic
Claude Sonnet 5.5
Favicon for google
Gemini 3.1 Pro Preview Custom Tools
Favicon for openai
GPT-6 Astra
Favicon for anthropic
Claude Sonnet 5.5
Favicon for google
Gemini 3.1 Pro Preview Custom Tools
Favicon for openai
GPT-6 Astra

Overview

Claude Sonnet 5.5
Author
Anthropic
Gemini 3.1 Pro Preview Custom Tools
Author
Google
GPT-6 Astra
Author
OpenAI
Claude Sonnet 5.5
Context length
1Mtokens
Gemini 3.1 Pro Preview Custom Tools
Context length
1.05Mtokens
GPT-6 Astra
Context length
1.05Mtokens
Claude Sonnet 5.5
Reasoning
Gemini 3.1 Pro Preview Custom Tools
Reasoning
GPT-6 Astra
Reasoning
Claude Sonnet 5.5
Input modalities
Gemini 3.1 Pro Preview Custom Tools
Input modalities
GPT-6 Astra
Input modalities
Claude Sonnet 5.5
Output modalities
Gemini 3.1 Pro Preview Custom Tools
Output modalities
GPT-6 Astra
Output modalities

Analysis

Claude Sonnet 5.5 vs Gemini 3.1 Pro Preview Custom Tools vs GPT-6 Astra: side-by-side summary

Claude Sonnet 5.5, Gemini 3.1 Pro Preview Custom Tools, and GPT-6 Astra are available through the OpenRouter API, so switching between them takes a model slug change rather than a new integration.

Claude Sonnet 5.5, from Anthropic, has a 1,000,000-token context window and is priced at $2/M tokens input, $10/M tokens output on OpenRouter.

Gemini 3.1 Pro Preview Custom Tools, from Google, has a 1,048,576-token context window and is priced at $2/M tokens input, $12/M tokens output on OpenRouter.

GPT-6 Astra, from OpenAI, has a 1,050,000-token context window and is priced at $10/M tokens input, $50/M tokens output on OpenRouter.

Claude Sonnet 5.5
Context window
1,000,000 tokens
Gemini 3.1 Pro Preview Custom Tools
Context window
1,048,576 tokens
GPT-6 Astra
Context window
1,050,000 tokens
Claude Sonnet 5.5
Price
$2/M tokens input, $10/M tokens output
Gemini 3.1 Pro Preview Custom Tools
Price
$2/M tokens input, $12/M tokens output
GPT-6 Astra
Price
$10/M tokens input, $50/M tokens output
Claude Sonnet 5.5
Provided by
Anthropic
Gemini 3.1 Pro Preview Custom Tools
Provided by
Google
GPT-6 Astra
Provided by
OpenAI
Claude Sonnet 5.5
Model page
Claude Sonnet 5.5 model details, providers and pricing
Gemini 3.1 Pro Preview Custom Tools
Model page
Gemini 3.1 Pro Preview Custom Tools model details, providers and pricing
GPT-6 Astra
Model page
GPT-6 Astra model details, providers and pricing
AttributeClaude Sonnet 5.5Gemini 3.1 Pro Preview Custom ToolsGPT-6 Astra
Context window1,000,000 tokens1,048,576 tokens1,050,000 tokens
Price$2/M tokens input, $10/M tokens output$2/M tokens input, $12/M tokens output$10/M tokens input, $50/M tokens output
Provided byAnthropicGoogleOpenAI
Model pageClaude Sonnet 5.5 model details, providers and pricingGemini 3.1 Pro Preview Custom Tools model details, providers and pricingGPT-6 Astra model details, providers and pricing