GPT-5.1 vs Gemini 3.1 Pro: Pricing Comparison

Compare pricing, capabilities, and costs for your LLM workloads.

OpenAI

GPT-5.1

Pricing (per 1M tokens)

Input$1.25
Output$10.00
Cached Input$0.1250

Context & Output

Context Window400K tokens
Max Output128K tokens

Capabilities

Categoryflagship
Multimodaltext + image
Fine-tuningNo
StreamingYes

Google

Gemini 3.1 Pro

Pricing (per 1M tokens)

Input$2.00
Output$12.00
Cached Input$0.2000
Batch Input$1.00
Batch Output$6.00

Context & Output

Context Window1M tokens
Max Output65.5K tokens

Capabilities

Categoryflagship
Multimodaltext + image + audio
Fine-tuningNo
StreamingYes

Quick Verdict

Cheaper Input Price

GPT-5.1

37.5% cheaper

Cheaper Output Price

GPT-5.1

16.7% cheaper

Larger Context Window

Gemini 3.1 Pro

+600K tokens

Cost Comparison

Sample workload: 1,000,000 input tokens + 1,000,000 output tokens

GPT-5.1

$11.25

$1.25/1M input + $10.00/1M output

Gemini 3.1 Pro

$14.00

$2.00/1M input + $12.00/1M output

GPT-5.1 is 19.6% cheaper for this workload.

Frequently Asked Questions

Which is cheaper, GPT-5.1 or Gemini 3.1 Pro?
For input tokens, GPT-5.1 is cheaper at $1.25 per 1M tokens. For output tokens, GPT-5.1 is cheaper at $10.00 per 1M tokens. The overall cost depends on your workload's input/output ratio.
What is the context window size of GPT-5.1 vs Gemini 3.1 Pro?
GPT-5.1 has a context window of 400K tokens, while Gemini 3.1 Pro has 1M tokens. Gemini 3.1 Pro supports a larger context window of 1M tokens, which is beneficial for processing longer documents.

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