Anthropic Claude Opus 5 (1M context) vs OpenAI GPT-5.6 Sol (1M)

Side-by-side comparison of pricing, context window, capabilities, and a real-cost sample workload.

Option A

Anthropic Claude Opus 5 (1M context)

by Anthropic
Context:1M
Input:$6.00 / 1M
Output:$30.00 / 1M
Released:2026-07
Option B

OpenAI GPT-5.6 Sol (1M)

by OpenAI
Context:1M
Input:$12.00 / 1M
Output:$72.00 / 1M
Released:2026-07

Detailed Comparison

DimensionAnthropic Claude Opus 5 (1M context)OpenAI GPT-5.6 Sol (1M)
ProviderAnthropicOpenAI
Context window TieTie1M1M
Input price ($/1M) Winner$6.00$12.00
Output price ($/1M) Winner$30.00$72.00
Sample workload cost Winner
1M input + 500K output tokens
$21.00 $48.00
Released TieTie2026-072026-07
Tokenizerclaude-4o200k_base

The verdict

On the dimensions we measured, Anthropic Claude Opus 5 (1M context) wins more often - particularly on cost-effectiveness for a typical 1M+0.5M workload.

Anthropic Claude Opus 5 (1M context) - Key features

The 1M-token context tier of Claude Opus 5. Same model, long-context premium pricing applied to requests above 200K input tokens. Built for whole-repository and whole-corpus work.

  • 1M token context window
  • Whole-repository reasoning
  • Long-context premium tier
  • Prompt caching support
  • Adaptive effort control

OpenAI GPT-5.6 Sol (1M) - Key features

OpenAI's Sol tier for GPT-5.6: a long-thinking configuration that spends far more reasoning tokens per request and tops OpenAI's own agentic and math evaluations. Priced as a premium reasoning endpoint.

  • Extended reasoning by default
  • ~1M token context window
  • 128K max output tokens
  • Parallel tool calling
  • Priority processing tier

How to choose

Estimate the real cost of either model for your prompts using our Token Calculator.