GPT-5.1 vs o3 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
OpenAI
o3 Pro
Pricing (per 1M tokens)
Input$20.00
Output$80.00
Context & Output
Context Window200K tokens
Max Output100K tokens
Capabilities
Categoryflagship
Multimodaltext + image
Fine-tuningNo
StreamingYes
Quick Verdict
Cheaper Input Price
GPT-5.1
93.8% cheaper
Cheaper Output Price
GPT-5.1
87.5% cheaper
Larger Context Window
GPT-5.1
+200K 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
o3 Pro
$100.00
$20.00/1M input + $80.00/1M output
GPT-5.1 is 88.8% cheaper for this workload.
Frequently Asked Questions
Which is cheaper, GPT-5.1 or o3 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 o3 Pro?
GPT-5.1 has a context window of 400K tokens, while o3 Pro has 200K tokens. GPT-5.1 supports a larger context window of 400K tokens, which is beneficial for processing longer documents.
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