Anthropic Claude Opus 4.8 (1M) vs Google Gemini 3.1 Pro (2M)

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

Option A

Anthropic Claude Opus 4.8 (1M)

by Anthropic
Context: 1M
Input: $5.00 / 1M
Output: $25.00 / 1M
Released: 2026-05
Option B

Google Gemini 3.1 Pro (2M)

by Google
Context: 2M
Input: $2.00 / 1M
Output: $12.00 / 1M
Released: 2026-02

Detailed Comparison

Dimension Anthropic Claude Opus 4.8 (1M) Google Gemini 3.1 Pro (2M)
Provider Anthropic Google
Context window Winner 1M 2M
Input price ($/1M) Winner $5.00 $2.00
Output price ($/1M) Winner $25.00 $12.00
Sample workload cost Winner
1M input + 500K output tokens
$17.50 $8.00
Released Winner 2026-05 2026-02
Tokenizer claude-4 gemini

The verdict

On the dimensions we measured, Google Gemini 3.1 Pro (2M) wins more often - particularly on cost-effectiveness for a typical 1M+0.5M workload.

Anthropic Claude Opus 4.8 (1M) - Key features

Anthropic's most capable Opus-tier model - highly autonomous, state-of-the-art on long-horizon agentic work, knowledge work and memory, with clearer, warmer writing. 1M context at standard pricing.

  • Adaptive thinking + effort (low→max)
  • State-of-the-art long-horizon agents
  • 128K max output tokens
  • 1M token context window
  • Strong code review & debugging

Google Gemini 3.1 Pro (2M) - Key features

Google's most capable Gemini Pro model with an industry-leading 2M token context window - ideal for large-document analysis and long multi-turn reasoning.

  • Industry-leading 2M context window
  • Deep multimodal reasoning
  • Strong tool use
  • Long-document analysis
  • Tiered long-context pricing

How to choose

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