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GPT-4 Turbo vs GPT-5.1

Compare OpenAI and OpenAI AI models

OpenAI
GPT-4 Turbo
vs
OpenAI
GPT-5.1

Cost Comparison (1000 input + 500 output tokens, 100 requests/day)

GPT-4 Turbo

Per Request:$0.025
Daily:$2.50
Monthly:$75.00
Yearly:$912.50

GPT-5.1

Per Request:$0.006250
Daily:$0.625
Monthly:$18.75
Yearly:$228.125

Cost Differences

$0.01875
Per Request
$1.875
Daily
$56.25
Monthly
$684.375
Yearly

GPT-5.1 costs less than GPT-4 Turbo

Feature Comparison

FeatureGPT-4 TurboGPT-5.1
ProviderOpenAIOpenAI
Input Price$10.00/1M tokens$1.25/1M tokens
Output Price$30.00/1M tokens$10.00/1M tokens
Context Window128,000 tokens1,000,000 tokens
Max Output4,096 tokens131,072 tokens
Categoryflagshipflagship
Capabilities
textvisioncode
textvisionaudiocodereasoning
Release Date4/9/202411/12/2025

GPT-4 Turbo vs GPT-5.1: Which Should You Choose?

Choosing between GPT-4 Turbo and GPT-5.1 depends on your priorities: cost efficiency, context length, or raw capability. GPT-5.1 is the more affordable option at $1.25/1M input tokens88% cheaper than GPT-4 Turbo. Meanwhile, GPT-5.1 offers a significantly larger context window at 1,000,000 tokens vs 128,000 for GPT-4 Turbo.

Both models are in the flagship category, making this a direct head-to-head comparison. At scale — say 10,000 requests per day — the cost difference adds up: GPT-5.1 would save you roughly $5,625.00/month compared to GPT-4 Turbo. For startups and indie developers, that difference can be significant.

Output costs matter too. GPT-4 Turbo charges $30.00/1M output tokens vs $10.00 for GPT-5.1. For generation-heavy workloads (content creation, code generation, summarization), output pricing often dominates your bill. GPT-5.1 has the edge here at $10.00/1M output tokens.

Multimodal capabilities: Both models support vision (image understanding), so you can send images alongside text prompts with either option.

Best Use Cases

Choose GPT-4 Turbo when:

  • • You're already using OpenAI's API ecosystem

Choose GPT-5.1 when:

  • • Budget is a primary concern
  • • You need a larger context window (1,000,000 tokens)
  • • You need more capabilities (audio, reasoning)
  • • You need longer outputs (up to 131,072 tokens)
  • • You're already using OpenAI's API ecosystem

Try Different Scenarios

Use the calculator below to see how costs change with different usage patterns

GPT-4 Turbo (OpenAI)

GPT-5.1 (OpenAI)

Start using GPT-4 Turbo today

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Start using GPT-5.1 today

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Frequently Asked Questions

Which is cheaper, GPT-4 Turbo or GPT-5.1?
GPT-5.1 is cheaper for input tokens at $1.25 per million tokens vs $10.00 for GPT-4 Turbo — that's 88% savings on input costs.
What is the context window difference between GPT-4 Turbo and GPT-5.1?
GPT-4 Turbo supports 128,000 tokens while GPT-5.1 supports 1,000,000 tokens — a difference of 872,000 tokens in favor of GPT-5.1.
Which model is better for AI Chatbot?
Both models support text. For ai chatbot, GPT-5.1 is the lower-cost option, while GPT-5.1 offers a larger context window (1,000,000 vs 128,000 tokens). Choose GPT-5.1 for budget sensitivity or GPT-5.1 for longer context tasks.
Which model has better overall pricing for heavy usage?
At 100 requests/day with 1,000 input and 500 output tokens each, GPT-4 Turbo costs about $75.00/month and GPT-5.1 costs about $18.75/month. Overall, GPT-5.1 has lower combined input + output rates ($1.25 in, $10.00 out) vs GPT-4 Turbo.

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