Standard Compute
Model Comparison 2026

Claude Opus 4.8 vs Gemini 3.1 Pro

Claude Opus 4.8
Anthropic · Frontier · Proprietary
$11/1M · 1M ctx
Gemini 3.1 Pro
Google · Frontier · Proprietary
$5.00/1M · 1.0M ctx

Community Vote

Pick a winner in each dimension — change your vote anytime.

Output Quality
Correctness and depth of what it produces
Agentic Ability
Tool calls, instruction-following, and multi-step tasks
Speed
Tokens per second and time-to-first-token
Value for $
How much capability you get per dollar
Reliability
Consistent results — fewer refusals, loops, and format breaks

Specs & Pricing, Side by Side

Spec
Opus 4.8
Gemini 3.1 Pro
Maker
Anthropic
Google
Blended price / 1M
$11
$5.00
Input / output
$5.00 in · $25 out / 1M tokens
$2.00 in · $12 out / 1M tokens
Context window
1M
1.0M
Open weights
No
No
Tool use
Yes
Yes
Reasoning
Yes
Yes
Output Quality
9.6
9.2
Agentic Ability
9.6
9.0
Speed
7.2
7.5
Value for $
7.5
8.1
Reliability
9.5
8.8

Pricing and capabilities synced from the OpenRouter catalogue. Scores are editorial (0–10).

Verdict: Opus 4.8 or Gemini 3.1 Pro?

Updated 2026-08-02

Choose Claude Opus 4.8 if you want hard, high-stakes coding and reasoning where quality matters more than cost. Choose Gemini 3.1 Pro if you want huge-context and multimodal work, and Gemini CLI users.

In our editorial scoring, Claude Opus 4.8 leads in 3 of five dimensions (output quality, agentic ability and reliability), while Gemini 3.1 Pro leads in 2. On price, Claude Opus 4.8 runs about $11 per 1M tokens (blended) and is proprietary; Gemini 3.1 Pro is about $5.00 and proprietary.

Where Opus 4.8 falls short
  • Among the most expensive models per token
  • Slower than lighter models on simple tasks
Full Opus 4.8 breakdown →
Where Gemini 3.1 Pro falls short
  • Tool use a touch behind Claude/GPT on some agents
  • Preview-tier stability varies
Full Gemini 3.1 Pro breakdown →

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