GPT-5.4 API

openai/gpt-5-4
A high-performance large language model engineered for advanced reasoning, multimodal understanding, long-context processing, and real-world coding tasks.
Context
1M tokens
Input
$2.5 / 1M tokens
Output
$15 / 1M tokens
Released
Mar 16, 2026

Overview

What exactly is GPT-5.4 API?

Unlike earlier GPT models that optimized primarily for fluency, GPT-5.4 pushes the frontier on structured reasoning and multi-step problem solving. It's not just generating plausible text, it's working through problems the way a thoughtful analyst would, weighing evidence, catching contradictions, and arriving at well-grounded conclusions.

The model is designed to operate at scale across enterprise workflows, developer toolchains, and research environments, handling everything from a quick summarization task to a multi-document analysis spanning thousands of tokens in a single pass.

Smarter, Faster, More Connected

GPT-5.4 isn’t just an upgrade, it’s a new generation of cognitive AI performance. Leveraging enhanced transformer architecture and a refined training pipeline, it delivers exceptional fluency, logical coherence, and contextual memory across text, image, and structured data inputs.

Key Highlights

  • Extended Context Window: Processes and remembers over a million tokens, ideal for handling entire books, technical documentation, or extensive chat histories.‍
  • Unmatched Reasoning Power: Solves complex logic chains, mathematical proofs, and programming tasks with near-human accuracy.‍
  • Adaptive Multimodality: Understands and generates text, code, images, and audio descriptions seamlessly.‍
  • Proactive Learning: Continually refines responses based on nuanced patterns in user input for a more responsive, human-like dialogue.

API Pricing

  • Input: $3.25
  • Cached input: $0.33
  • Output: $19.50

Technical specifications

For developers and engineers evaluating GPT-5.4 for integration, here's a closer look at what the model brings to the table technically.

  • Model family: GPT-5 series (OpenAI)
  • Architecture: Transformer-based autoregressive language model with RLHF fine-tuning
  • Modalities: Text + image input; text output
  • ‍Context window: 128,000+ tokens — supports book-length documents in a single pass
  • Output length: Extended output with coherence maintained across thousands of tokens
  • Supported languages: 100+ natural languages; strong multilingual performance
  • Primary use cases: Reasoning, coding, analysis, document QA, conversational AI, agentic tasks

Core Capabilities

Long-Context Intelligence

GPT-5.4 introduces persistent context tracking, preserving meaning across massive documents and multi-turn conversations. This capability empowers professional applications such as technical manuals, legal analyses, or serialization of creative writing without loss of coherence or tone.

Example: GPT-5.4 can analyze a 200-page research report, summarize its core insights, and generate concise recommendations tailored to different audiences, from scientists to investors.

Multimodal Reasoning Engine

Beyond text, GPT-5.4 handles visual elements, numeric data, and symbolic logic natively. It can describe images, interpret charts, or generate structured JSON outputs in a single prompt. This integrated reasoning pipeline supports advanced workflows in AI-driven design, synthetic biology, and data visualization.

Performance at Scale

Powered by optimized inference algorithms and distributed computing, GPT-5.4 delivers high throughput and low latency, even under enterprise workloads. It’s engineered to meet the rigorous demands of global-scale applications from intelligent agents to autonomous analytical systems.

Ethical Intelligence by Design

OpenAI continues its commitment to responsible AI with transparent alignment procedures, content safety layers, and improved detection of hallucination and bias. GPT-5.4 operates under a refined Reinforcement Learning from Human Feedback (RLHF) model to ensure safer, more factual interactions.

Who is GPT-5.4 built for?

GPT-5.4 is a professional-grade model. It's not a casual chatbot, it's infrastructure. The use cases where it genuinely shines reflect that positioning.

  • Software developers: Generating, debugging, and reviewing code across languages and frameworks, including architecture decisions and refactoring at scale.
  • Research & academia: Literature synthesis, hypothesis analysis, structured summarization, and working through complex multi-source datasets.
  • Product & content teams: High-quality long-form writing, structured content generation, tone-consistent brand copy, and multilingual localization.
  • Data & analytics: Natural language to SQL, report narration, insight extraction from large datasets, and analytical reasoning over structured inputs.

When to stick with GPT-4o or smaller models

GPT-5.4 is not always the right tool. For high-volume, latency-sensitive tasks — simple classification, short-form Q&A, real-time chat — a lighter model often makes more sense on cost and speed. GPT-5.4 earns its place when output quality is mission-critical and the task genuinely demands deep reasoning or long-context comprehension.

Uptime and performance

  • Uptime (24h): 63.0%
  • Uptime (7d): 95.0%
  • Availability (24h): 15.0%
  • Error rate (24h): 85.0%
  • End-to-end latency (24h median): 26.8s
  • Time to first token (24h median): 1.3s
  • Throughput (24h median): 45.0 tok/s

Measured on the AI/ML API gateway across live traffic. Figures are medians unless stated. Last updated 2026-10-12.

Use cases

GPT-5.4 is documented as suited to computer-use workflows, including operating computers and carrying out complex workflows across applications. It is also suited to coding tasks, especially writing code to operate computers with libraries like Playwright and issuing mouse and keyboard commands from screenshots.

It is documented as suited to deep web research, particularly for highly specific queries, while maintaining context over longer thinking. It is also suited to professional work involving spreadsheets, presentations, and documents, where it helps get complex work done accurately and efficiently.

How to use GPT-5.4 API

Install any OpenAI-compatible SDK, point it at api.aimlapi.com/v1, and set the model to openai/gpt-5-4.
import requests

r = requests.post(
    "https://api.aimlapi.com/v1/chat/completions",
    headers={"Authorization": "Bearer " + AIMLAPI_KEY},
    json={
      "model": "openai/gpt-5-4",
      "messages": [
        {
          "role": "user",
          "content": "Hello!"
        }
      ]
    },
)
print(r.json())
const r = await fetch("https://api.aimlapi.com/v1/chat/completions", {
  method: "POST",
  headers: {
    Authorization: `Bearer ${process.env.AIMLAPI_KEY}`,
    "Content-Type": "application/json",
  },
  body: JSON.stringify({
    "model": "openai/gpt-5-4",
    "messages": [
      {
        "role": "user",
        "content": "Hello!"
      }
    ]
  }),
});
console.log(await r.json());
curl -X POST https://api.aimlapi.com/v1/chat/completions \
  -H "Authorization: Bearer $AIMLAPI_KEY" \
  -H "Content-Type: application/json" \
  -d '{"model":"openai/gpt-5-4","messages":[{"role":"user","content":"Hello!"}]}'

OpenAI-compatible — swap the base URL and it works with your existing SDK.

GPT-5.4 API Pricing

TypePrice
Input
$2.5 / 1M tokens
Output
$15 / 1M tokens
Cached input
$0.25 / 1M tokens

GPT-5.4 Benchmarks

BenchmarkScoreWhat it measuresSourceRetrieved
Intelligence
39
Composite score across standardised reasoning, knowledge and problem-solving evaluations, measured independently by Artificial AnalysisSourceSeptember 12, 2026
Coding
71.1
Composite score across standardised coding evaluations, measured independently by Artificial AnalysisSourceSeptember 12, 2026

GPT-5.4 vs other models

ModelInputOutputContextBest for
GPT-5.4
This page
$2.5 / 1M tokens
$15 / 1M tokens
1M tokens
Reasoning + agents
$5 / 1M tokens
$30 / 1M tokens
1M tokens
Reasoning + agents
$2 / 1M tokens
$10 / 1M tokens
1M tokens
Balanced coding + agents
$3 / 1M tokens
$15 / 1M tokens
1M tokens
Long-context, multimodal & agentic workflows
$1.5 / 1M tokens
$9 / 1M tokens
1M tokens
Reasoning + agents

Frequently asked questions

GPT-5.4 has a 1,050,000 tokens context window and can return up to 128,000 tokens.

GPT-5.4 takes image, text as input and returns text.

Use openai/gpt-5-4 as the model id. Requests go to https://api.aimlapi.com/v1/chat/completions.

GPT-5.4 is priced at input $3.25 / 1M tokens, output $19.5 / 1M tokens, cached input $0.325 / 1M tokens.

Yes, GPT-5.4 can stream responses as they are generated.

Yes, GPT-5.4 accepts image input alongside text.

GPT-5.4 was built by OpenAI.

Start building with GPT-5.4

Get API Key
1000+ models, one API.