Model Comparison 2026

Gemini 3.1 Pro vs Grok 4.3

Gemini 3.1 Pro
Google · Frontier · Proprietary
$5.00/1M · 1.0M ctx
Grok 4.3
xAI · Frontier · Proprietary
$1.63/1M · 1M 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
Gemini 3.1 Pro
Grok 4.3
Maker
Google
xAI
Blended price / 1M
$5.00
$1.63
Input / output
$2.00 in · $12 out / 1M tokens
$1.25 in · $2.50 out / 1M tokens
Context window
1.0M
1M
Open weights
No
No
Tool use
Yes
Yes
Reasoning
Yes
Yes
Output Quality
9.2
8.7
Agentic Ability
9.0
8.2
Speed
7.5
8.0
Value for $
8.1
8.6
Reliability
8.8
8.4

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

Verdict: Gemini 3.1 Pro or Grok 4.3?

Updated 2026-06-22

Choose Gemini 3.1 Pro if you want huge-context and multimodal work, and Gemini CLI users. Choose Grok 4.3 if you want frontier capability on a tighter budget.

In our editorial scoring, Gemini 3.1 Pro leads in 3 of five dimensions (output quality, agentic ability and reliability), while Grok 4.3 leads in 2. On price, Gemini 3.1 Pro runs about $5.00 per 1M tokens (blended) and is proprietary; Grok 4.3 is about $1.63 and proprietary.

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 →
Where Grok 4.3 falls short
  • Tool-use polish behind Claude/GPT
  • Smaller ecosystem
Full Grok 4.3 breakdown →

The model is half the story — the agent is the other half

The model picks the moves; the agent runs the loop, the tools, and the guardrails. Once you've chosen a model, see which agent gets the most out of it.

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