Gemini 3.1 Pro vs Grok 4.3: API Pricing
Input and output token rates, context windows, and real monthly cost for Gemini 3.1 Pro (Google) and Grok 4.3 (xAI), side by side. Prices are standard on-demand rates as of June 2026.
The short answer
For a typical coding-agent workload (60M in / 12M out per month), Grok 4.3 is the cheaper option at $105/mo versus $264/mo for Gemini 3.1 Pro - about 60% less (2.5× cheaper). On the headline sticker of 1M input + 1M output, Gemini 3.1 Pro is $14.00 and Grok 4.3 is $3.75.
Rates at a glance
| Gemini 3.1 Pro | Grok 4.3 | |
|---|---|---|
| Input ($/1M tokens) | $2.00 | $1.25 |
| Output ($/1M tokens) | $12.00 | $2.50 |
| Blended (1M in + 1M out) | $14.00 | $3.75 |
| Context window | 1,000K | 1,000K |
| Type | Proprietary | Proprietary |
| Provider | xAI |
Monthly cost by workload
Estimated monthly API spend at each workload's token volume. Output usually costs several times input, so the winner can flip with your mix.
| Workload | Gemini 3.1 Pro | Grok 4.3 | Cheaper |
|---|---|---|---|
| Chatbot / assistant10M in / 3M out | $56.00/mo | $20.00/mo | Grok 4.3 |
| Coding agent60M in / 12M out | $264/mo | $105/mo | Grok 4.3 |
| RAG / summarization40M in / 4M out | $128/mo | $60.00/mo | Grok 4.3 |
| Batch / classification20M in / 2M out | $64.00/mo | $30.00/mo | Grok 4.3 |
Want your own in/out split? Use the full interactive comparator to rank every model and provider for your exact workload.
Frequently asked questions
Is Gemini 3.1 Pro or Grok 4.3 cheaper?
It depends on your input/output mix, but for a typical coding-agent workload (60M in / 12M out per month) Grok 4.3 costs $105/mo versus $264/mo for Gemini 3.1 Pro - about 60% less (2.5x). On the headline sticker (1M input + 1M output), Gemini 3.1 Pro is $14.00 and Grok 4.3 is $3.75.
What are the token rates for Gemini 3.1 Pro and Grok 4.3?
Gemini 3.1 Pro (Google) is $2.00 per 1M input and $12.00 per 1M output. Grok 4.3 (xAI) is $1.25 per 1M input and $2.50 per 1M output. These are standard on-demand rates, not cached or batch.
Is Gemini 3.1 Pro or Grok 4.3 open-weight?
Gemini 3.1 Pro is proprietary and Grok 4.3 is proprietary. Both are closed models billed only through their owner's API.
What context window do Gemini 3.1 Pro and Grok 4.3 support?
Gemini 3.1 Pro supports 1,000K tokens and Grok 4.3 supports 1,000K tokens. Some models also step up pricing past a size threshold - check the source pricing pages for long-context tiers.
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