GPT-5 API

GPT-5 is OpenAI's most advanced language model with a 400K token context window and superior reasoning capabilities.

Modalities: Text, ImageText
In / Out price: $1.25/$10per 1M
Context window: 400K tokens
Released: Aug 7, 2025

GPT-5 overview

GPT-5 by OpenAI

It delivers enhanced reasoning, deeper memory retention, and superior accuracy across diverse domains such as coding, scientific analysis, and large-scale document processing, with robust safety and bias mitigation systems.

GPT-5 specs

Model ID: openai/gpt-5-2025-08-07
Developer: OpenAI
Context window: 400,000 tokens
Max output: 128,000 tokens
Input: Text, Image
Output: Text
API: OpenAI-compatible, base URL https://api.aimlapi.com/v1

What Is GPT-5 API?

GPT-5 is OpenAI’s most capable large language model to date. Launched on August 7, 2025, it introduces a unified architecture that intelligently routes between a fast everyday model, a deeper “thinking” reasoning engine, and a real-time decision layer that knows exactly when to go deep.

With a massive 400,000-token context window, native vision support, and major leaps in instruction following, tool use, and factual accuracy. It crushes benchmarks in coding, math, scientific reasoning, and long-context analysis while staying fast and cost-effective for high-volume workloads.

Technical Specifications & Performance

Context window: 400,000 tokens (input + output combined)
Multimodal: Text + vision (images up to industry-leading file sizes)
Reasoning modes: Adaptive + explicit control (minimal, low, medium, high, xhigh on newer snapshots)

Performance Benchmarks

Speed & Latency: GPT-5 delivers faster inference times compared to GPT-4.1, benefiting from architectural optimizations and pricing incentives for cached input tokens.
Accuracy: Improved few-shot learning and factual correctness across benchmarks in coding, legal document analysis, and scientific domains.
Multilingual support: Expanded language coverage beyond GPT-4.1 capabilities, with superior translation and culturally nuanced understanding.

Architecture Breakdown

GPT-5 is built on an advanced transformer framework with optimized attention mechanisms and energy-efficient Mixture of Experts (MoE) layers. Recursive training and enhanced context management enable dynamic focus on salient information, improving both computational speed and accuracy over prior generation models.

Built-In Adaptive Reasoning

GPT-5 automatically decides when to use “thinking” mode for hard problems. Need step-by-step logic on a tricky algorithm? It goes deep. Need a fast answer? It stays snappy. You can also explicitly control reasoning effort (minimal → high) for predictable behavior and cost.

Massive 400K Context Window

Process entire codebases, 200-page PDFs, hours of meeting transcripts, or long customer histories in a single prompt. No more chunking, summarizing, or losing the plot halfway through.

Use cases

Software engineering workflows, including advanced code generation, debugging, and multi-file refactoring.
Large-scale document analysis for sectors like legal, finance, healthcare, and regulatory compliance.
Multimodal content creation and understanding, blending text and images seamlessly.
Creative writing, education, and research assistance with multi-step instruction execution and detailed reasoning.

Capabilities

Function calling
Streaming
Structured outputs
Reasoning
Web search

GPT-5 benchmarks by Artificial Analysis

See how GPT-5 compares in generation speed. Data retrieved Nov 3, 2026.

Speed#94 / 219120Output tokens / second Humanity's Last Exam#100 / 45828.5%Score GPQA Diamond#91 / 43985.4%Score AA-LCR#76 / 39178.2%Score

Speed

Output tokens / second

Benchmark results

Compare 17 models available on AI/ML API across 5 independent benchmarks.

Humanity's Last Exam

Expert-written questions across academic subjects.

GPT-5 API pricing

GPT-5 pricing in US dollars
Usage	Price	Unit
Input	$1.25	1M tokens
Output	$10	1M tokens
Cached input	$0.125	1M tokens

Prices from the AI/ML API price list, checked on Nov 4, 2026.

GPT-5 vs other models: token prices

AI/ML API input and output rates for 5 models, per million tokens.

AI/ML API model prices in USD per million tokens
Model	Input	Output
GPT-5	$1.25	$10
GPT-6 Luna	$0.1	$0.5
GPT-6.1 Terra	$1	$5
GPT-6.1 Sol	$2	$10
GPT-6.1 Terra Pro	$2.12	$10.58

How to use the GPT-5 API

View docs

Build with your agent

Give your agent the model details, code and documentation.

1Get your API key

Create API key

export AIMLAPI_KEY="8f2b4c7d9a1e6b3f…"

2Make your first request

curl 'https://api.aimlapi.com/v1/chat/completions' \
  -H "Authorization: Bearer $AIMLAPI_KEY" \
  -H 'Content-Type: application/json' \
  -d '{
  "model": "openai/gpt-5-2025-08-07",
  "messages": [
    {
      "role": "user",
      "content": "Write a haiku about the ocean."
    }
  ]
}'

import os
import requests

headers = {
    "Authorization": f"Bearer {os.environ['AIMLAPI_KEY']}",
    "Content-Type": "application/json",
}
payload = {
    "model": "openai/gpt-5-2025-08-07",
    "messages": [
        {
            "role": "user",
            "content": "Write a haiku about the ocean."
        }
    ]
}

response = requests.post("https://api.aimlapi.com/v1/chat/completions", headers=headers, json=payload, timeout=120)
response.raise_for_status()
print(response.json())

const response = 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-5-2025-08-07",
    "messages": [
      {
        "role": "user",
        "content": "Write a haiku about the ocean."
      }
    ]
  }),
});

if (!response.ok) throw new Error(`HTTP ${response.status}`);
console.log(await response.json());

All posts

GPT-5 FAQ

What is the context window of GPT-5?

GPT-5 has a 400,000 tokens context window and can return up to 128,000 tokens.

What inputs and outputs does GPT-5 support?

GPT-5 takes image, text as input and returns text.

What is the model ID for GPT-5?

Use openai/gpt-5-2025-08-07 as the model id. Requests go to https://api.aimlapi.com/v1/chat/completions.

How much does GPT-5 cost?

GPT-5 costs $1.25 input and $10 output per 1M tokens on AI/ML API, billed as you go with no subscription.

Does GPT-5 support streaming?

Yes, GPT-5 can stream responses as they are generated.

Can GPT-5 read images?

Yes, GPT-5 accepts image input alongside text.

Who created GPT-5?

GPT-5 was built by OpenAI.

Start building with GPT-5

Get API key

GPT-5 API

openai/gpt-5-2025-08-07

Build with your agent

Give your agent the model details, code and documentation.

1Get your API key

Create API key

export AIMLAPI_KEY="8f2b4c7d9a1e6b3f…"

2Make your first request

curl 'https://api.aimlapi.com/v1/chat/completions' \
  -H "Authorization: Bearer $AIMLAPI_KEY" \
  -H 'Content-Type: application/json' \
  -d '{
  "model": "openai/gpt-5-2025-08-07",
  "messages": [
    {
      "role": "user",
      "content": "Write a haiku about the ocean."
    }
  ]
}'

import os
import requests

headers = {
    "Authorization": f"Bearer {os.environ['AIMLAPI_KEY']}",
    "Content-Type": "application/json",
}
payload = {
    "model": "openai/gpt-5-2025-08-07",
    "messages": [
        {
            "role": "user",
            "content": "Write a haiku about the ocean."
        }
    ]
}

response = requests.post("https://api.aimlapi.com/v1/chat/completions", headers=headers, json=payload, timeout=120)
response.raise_for_status()
print(response.json())

const response = 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-5-2025-08-07",
    "messages": [
      {
        "role": "user",
        "content": "Write a haiku about the ocean."
      }
    ]
  }),
});

if (!response.ok) throw new Error(`HTTP ${response.status}`);
console.log(await response.json());

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GPT-5 API

GPT-5 overview

GPT-5 by OpenAI

GPT-5 specs

What Is GPT-5 API?

Technical Specifications & Performance

Performance Benchmarks

Architecture Breakdown

Built-In Adaptive Reasoning

Massive 400K Context Window

Use cases

Capabilities

GPT-5 benchmarks by Artificial Analysis

Speed

Benchmark results

Humanity's Last Exam

GPQA Diamond

AA-LCR

IFBench

τ²-Bench Telecom

GPT-5 API pricing

GPT-5 vs other models: token prices

How to use the GPT-5 API

Build with your agent

1Get your API key

2Make your first request

Related articles

GPT-5 FAQ

Start building with GPT-5

GPT-5 API

Build with your agent

1Get your API key

2Make your first request

GPT-5 API

GPT-5 overview

GPT-5 by OpenAI

GPT-5 specs

What Is GPT-5 API?

Technical Specifications & Performance

Performance Benchmarks

Architecture Breakdown

Built-In Adaptive Reasoning

Massive 400K Context Window

Use cases

Capabilities

Speed

Benchmark results

Humanity's Last Exam

GPQA Diamond

AA-LCR

IFBench

τ²-Bench Telecom

GPT-5 API pricing

GPT-5 vs other models: token prices

How to use the GPT-5 API

Build with your agent

1Get your API key

2Make your first request

Models similar to GPT-5

GPT-6.1 Terra

GPT-6.1 Terra Pro

GPT-6.1 Sol

Grok 4.20

Grok 4.3

Grok 4.20 Non-Reasoning

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