GPT-5.1 vs GPT-4.1: 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

GPT-4.1

Pricing (per 1M tokens)

Input$2.00
Output$8.00
Cached Input$0.5000
Batch Input$1.00
Batch Output$4.00

Context & Output

Context Window1.0M tokens
Max Output32.8K tokens

Capabilities

Categoryflagship
Multimodaltext + image
Fine-tuningYes
StreamingYes

Quick Verdict

Cheaper Input Price

GPT-5.1

37.5% cheaper

Cheaper Output Price

GPT-4.1

20.0% cheaper

Larger Context Window

GPT-4.1

+647.6K 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

GPT-4.1

$10.00

$2.00/1M input + $8.00/1M output

GPT-4.1 is 11.1% cheaper for this workload.

Frequently Asked Questions

Which is cheaper, GPT-5.1 or GPT-4.1?
For input tokens, GPT-5.1 is cheaper at $1.25 per 1M tokens. For output tokens, GPT-4.1 is cheaper at $8.00 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 GPT-4.1?
GPT-5.1 has a context window of 400K tokens, while GPT-4.1 has 1.0M tokens. GPT-4.1 supports a larger context window of 1.0M tokens, which is beneficial for processing longer documents.

Need more tools?

Explore our complete suite of LLM calculators and comparison tools.