GPT-5.1 (high) (high)

Elite intelligence meets impressive speed, but watch the verbosity.

GPT-5.1 (high) (high)

A top-tier multimodal model from OpenAI, offering exceptional intelligence and speed with a massive context window, balanced by moderate pricing and high verbosity.

Multimodal400k ContextHigh IntelligenceFast OutputProprietaryKnowledge Cutoff: Sep 2024

GPT-5.1 (high) represents a significant leap forward in the landscape of large language models, positioning itself as a premier offering from OpenAI. This model distinguishes itself not just through raw intellectual horsepower but through a finely tuned balance of speed, massive context processing, and advanced multimodality. It is designed for developers and enterprises tackling complex, high-stakes problems that demand nuanced understanding, sophisticated reasoning, and the ability to synthesize information from vast and varied sources. With the ability to process both text and images and generate them in kind, it unlocks a new class of applications, from detailed visual analysis to the creation of rich, illustrated content.

In our comprehensive benchmarking, GPT-5.1 (high) achieved a remarkable score of 70 on the Artificial Analysis Intelligence Index, placing it at an elite rank of #4 out of 101 models. This score, significantly above the class average of 44, underscores its advanced capabilities in areas like logic, reasoning, and comprehension. However, this intelligence comes with a notable characteristic: extreme verbosity. During the intelligence evaluation, the model generated a staggering 81 million tokens, nearly three times the average of 28 million. This tendency to provide exhaustive, detailed responses is a double-edged sword. While beneficial for tasks requiring thoroughness, it can lead to runaway costs and information overload if not carefully managed through precise prompting and parameter controls.

Performance-wise, GPT-5.1 (high) is a powerhouse. It delivers an output speed of approximately 125 tokens per second, placing it among the fastest models in its class and well ahead of the average (71 t/s). This rapid generation makes for a fluid user experience in many applications. The trade-off for this speed appears in its latency, or time to first token (TTFT), which stands at a high 23.69 seconds. This means users will experience a noticeable pause before the model begins generating its response, a critical factor to consider for real-time, interactive applications. For asynchronous tasks like report generation or batch processing, this delay is less of a concern, but for a chatbot, it could be a deal-breaker.

From a cost perspective, GPT-5.1 (high) presents a complex picture. The input price of $1.25 per million tokens is moderately priced and more affordable than the class average of $1.60. The output price of $10.00 per million tokens sits exactly at the class average. The danger lies in the combination of this 8-to-1 output-to-input price ratio and the model's high verbosity. A short prompt can easily trigger a long, expensive response. Our own evaluation on the Intelligence Index cost a total of $859.06, a testament to how quickly costs can accumulate when the model is allowed to generate text freely. This makes cost-control strategies not just a recommendation, but a necessity for any production deployment.

Scoreboard

Intelligence

70 (4 / 101)

Ranks in the top 4% for intelligence, demonstrating elite reasoning and comprehension capabilities for complex tasks.
Output speed

124.7 tokens/s

Significantly faster than the class average of 71 t/s, making it suitable for applications where generation speed is critical.
Input price

$1.25 / 1M tokens

More affordable than the class average of $1.60, but high verbosity can still lead to high total costs.
Output price

$10.00 / 1M tokens

Priced at the class average, but its high token output can lead to unexpectedly large bills if not controlled.
Verbosity signal

81M tokens

Generated nearly 3x the average token count (28M) in our tests, indicating a tendency for very detailed responses.
Provider latency

23.69 seconds

Time to first token is very high. Users will experience a noticeable delay before output begins.

Technical specifications

Spec Details
Model Owner OpenAI
License Proprietary
Context Window 400,000 tokens
Knowledge Cutoff September 2024
Input Modalities Text, Image
Output Modalities Text, Image
Intelligence Index Score 70 / 100
Intelligence Rank #4 / 101
Output Speed ~125 tokens/s
Latency (TTFT) ~24 seconds
Input Price $1.25 / 1M tokens
Output Price $10.00 / 1M tokens

What stands out beyond the scoreboard

Where this model wins
  • Elite Intelligence: Its top-tier ranking makes it ideal for complex analytical and reasoning tasks where accuracy and depth are paramount.
  • High-Speed Generation: Once it starts, the model produces text at a very high rate, creating a fluid experience for use cases that can tolerate the initial latency.
  • Massive Context Window: The ability to process up to 400,000 tokens allows it to analyze and synthesize information from extremely large documents, such as entire codebases or lengthy financial reports.
  • Advanced Multimodality: Natively handling both text and images for input and output enables sophisticated applications in visual Q&A, content creation, and data analysis.
  • Competitive Input Pricing: The cost to send information to the model is lower than many competitors in its intelligence class, making it more affordable for tasks involving large inputs.
Where costs sneak up
  • Extreme Verbosity: The model's default behavior is to be exhaustive, which can triple output token counts and costs compared to less verbose models.
  • High Latency: A ~24-second delay before the first token appears makes it unsuitable for many real-time, user-facing applications like chatbots or instant assistants.
  • Expensive Output Ratio: With output tokens costing 8 times more than input tokens, the model's high verbosity directly translates into disproportionately high operational costs.
  • The Large Context Trap: While powerful, using the full 400k context window is expensive. A single full-context prompt costs $0.50 in input fees alone, before any output is generated.
  • Proprietary Lock-in: As a closed-source model, users are dependent on the provider's API, pricing structure, and terms of service, limiting flexibility and control.

Provider pick

Choosing a provider for GPT-5.1 (high) is a subtle decision, as both benchmarked providers, OpenAI and Databricks, offer nearly identical pricing and performance. The differences are marginal, meaning the best choice often depends more on your existing cloud ecosystem and specific priorities than on a clear-cut performance winner.

Priority Pick Why Tradeoff to accept
Lowest Latency OpenAI Marginally faster time-to-first-token in our tests (23.69s vs. 31.01s). The difference is small and may not be a deciding factor for asynchronous workloads.
Highest Throughput OpenAI Slightly faster output speed at 125 tokens/s compared to Databricks' 120 t/s. A 4% speed advantage that is unlikely to be perceptible to end-users.
Lowest Price Tie Both providers have identical list prices for input ($1.25/M) and output ($10.00/M) tokens. No cost advantage either way. Choice may depend on negotiated rates or bundled platform services.
Platform Integration Databricks The ideal choice for teams already embedded in the Databricks Data Intelligence Platform, allowing for a unified workflow. Adds another vendor and potential integration complexity if you are not already a Databricks customer.

Performance metrics are based on benchmarks conducted by Artificial Analysis. Blended price is a weighted average reflecting typical usage patterns. Your actual costs and performance may vary based on workload and negotiated pricing.

Real workloads cost table

Theoretical prices per million tokens can be abstract. To make the cost of using GPT-5.1 (high) more tangible, we've estimated the expense for several real-world scenarios. These examples highlight how the model's high verbosity and 8:1 output-to-input price ratio directly impact your budget, even for seemingly small tasks.

Scenario Input Output What it represents Estimated cost
Customer Support Email Triage 500 tokens 2,000 tokens Summarizing and categorizing an incoming customer email. ~$0.021
Complex Document Summary 100,000 tokens 5,000 tokens Condensing a 75-page report into a multi-page executive summary. ~$0.175
Creative Content Generation 200 tokens 4,000 tokens Writing a detailed blog post from a short prompt. ~$0.040
Multi-turn Chatbot Session 3,000 tokens (total) 15,000 tokens (total) A 10-turn conversation where the model's responses are much longer than the user's. ~$0.154
Image Analysis & Description 1,500 tokens (image + prompt) 8,000 tokens Analyzing a complex diagram and providing a highly detailed textual explanation. ~$0.082

The consistent theme across all workloads is the disproportionate cost of output. In every scenario, the cost of the generated text far exceeds the cost of the prompt. This is a direct consequence of the model's natural verbosity combined with the 8x price premium on output tokens, making output management the single most important factor in controlling costs.

How to control cost (a practical playbook)

Given GPT-5.1 (high)'s tendency for high verbosity and expensive output, proactive cost management is essential. Implementing specific strategies in your application logic can prevent runaway expenses and ensure a sustainable operational budget. Below are several techniques to control token generation and optimize spending without sacrificing quality.

Enforce `max_tokens` Limits

The most direct way to control costs is to set a hard limit on the number of tokens the model can generate. By using the max_tokens parameter in your API call, you can prevent the model from producing excessively long and expensive responses.

  • Use Case: For generating summaries or short descriptions, set a low max_tokens value (e.g., 150) to guarantee brevity.
  • Best Practice: Calculate a reasonable maximum length for each specific task and enforce it programmatically. Do not rely on a single, global limit.
Engineer Prompts for Conciseness

You can guide the model toward shorter answers through careful prompt engineering. Explicit instructions to be brief are often respected and can significantly reduce output token count.

  • Example Instructions: "Summarize the following in three bullet points." or "Answer in a single paragraph." or "Be concise."
  • Benefit: This method helps control costs while also improving the user experience by providing more focused and less rambling answers.
Leverage the Large Context Window Wisely

The 400k context window is a powerful tool, but filling it unnecessarily is a costly mistake. Instead of passing entire documents for every query, use more efficient techniques.

  • Strategy 1 (RAG): Use Retrieval-Augmented Generation to find the most relevant snippets from your documents and only include those in the prompt.
  • Strategy 2 (Summarization): For long conversations, create rolling summaries of the dialogue to keep the context relevant without letting the token count grow indefinitely.
Use Function Calling for Structured Data

When you need structured data (like JSON), prompting the model to generate it as plain text is unreliable and token-inefficient. Use the API's built-in function calling or tool use features instead.

  • Advantage: The model returns a well-formatted, predictable object that is less verbose and requires no risky string parsing.
  • Result: This leads to more robust application logic and lower token costs, as the model's output is constrained to the defined function signature.

FAQ

What is GPT-5.1 (high)?

GPT-5.1 (high) is a premier, proprietary large language model from OpenAI. It is distinguished by its top-tier intelligence, high-speed output, massive 400k token context window, and multimodal capabilities (processing both text and images).

How does it compare to other models on the market?

It ranks among the most intelligent and fastest models available. However, its key differentiators are also its primary trade-offs: its high intelligence is paired with extreme verbosity, and its fast output is preceded by high latency. Its pricing is moderate, but costs can escalate quickly due to its verbose nature.

What does "multimodal" mean for this model?

Multimodality means the model can natively understand and generate more than one type of data. GPT-5.1 (high) can accept a combination of text and images as input and can produce both text and images as output, enabling more complex and creative applications.

Is the high latency a significant problem?

It depends on the use case. For real-time, interactive applications like a customer service chatbot, a ~24-second wait for a response can be unacceptable. For asynchronous, backend tasks like generating a report or summarizing a document, this initial delay is often negligible.

What is the best way to manage the cost of using GPT-5.1 (high)?

The most effective cost-control measures directly target its high verbosity. The two best strategies are: 1) Programmatically enforcing output limits using the max_tokens parameter, and 2) Using precise prompt engineering to explicitly request concise, brief answers.

Who is the best provider for this model?

The performance and pricing between OpenAI and Databricks are nearly identical. OpenAI has a slight edge on latency and speed, but the difference is minimal. The best choice often comes down to non-performance factors, such as existing platform integrations (favoring Databricks) or a desire to work directly with the model's creator (favoring OpenAI).

What does the "(high)" in the name signify?

The "(high)" designation likely indicates that this is a specific variant of the base GPT-5.1 model. This version may be fine-tuned or optimized for higher performance on complex reasoning and intelligence benchmarks, potentially at the expense of other metrics like latency or cost-efficiency.


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