LLM Reference
OpenAI API

GPT-5 on OpenAI API

GPT-5 · OpenAI

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Last refreshed 2026-05-10. Next refresh: weekly.

Why use GPT-5 on OpenAI API?

OpenAI API offers GPT-5 with pay-as-you-go pricing at $1.25/1M input tokens. OpenAI is a leading AI research and deployment company dedicated to developing safe and beneficial artificial general intelligence (AGI) for humanity.

Compare GPT-5 across 4 providers to find the best fit for your use case
Input / 1M
$1.25
Output / 1M
$10.00
Cache
read $0.125
Batch
-50% · in $0.625 / out $5.00

Setup recipe

Python + curl
Install
pip install openai
Auth
export OPENAI_API_KEY=...
Call
import os
from openai import OpenAI
client = OpenAI()  # reads OPENAI_API_KEY from env
response = client.chat.completions.create(
Model ID
gpt-5

Request example

import os
from openai import OpenAI

client = OpenAI()  # reads OPENAI_API_KEY from env
response = client.chat.completions.create(
    model="gpt-5",
    messages=[{"role": "user", "content": "Hello"}]
)
print(response.choices[0].message.content)

Gotchas

  • Use the model slug directly, e.g. "gpt-4o" or "gpt-4.1-mini".
  • The examples expect OPENAI_API_KEY; rename it only if your application config maps the new variable.

Compare GPT-5 Across Providers

ProviderInput (per 1M)Output (per 1M)
Replicate API$1.25$10.00
OpenRouter$1.25$10.00
OpenAI API$1.25$10.00
Vercel AI Gateway$1.25$10.00

Pricing

TypePrice (per 1M)
Input tokens$1.25
Output tokens$10.00

Capabilities

VisionMultimodalReasoningFunction CallingTool UseStructured OutputsCode ExecutionPrompt CachingBatch API

About GPT-5

OpenAI's previous intelligent reasoning model with configurable reasoning effort. Released August 2025. Supports minimal, low, medium, and high reasoning levels. Succeeded by GPT-5.1 and later models.

FAQ

What does GPT-5 cost on OpenAI API?

On OpenAI API, GPT-5 costs $1.25 per 1M input tokens and $10.00 per 1M output tokens.

What is the context window for GPT-5 on OpenAI API?

GPT-5 supports a 400k token context window on OpenAI API.

How does OpenAI API compare to other GPT-5 providers?

GPT-5 is available from 4 providers. The cheapest input pricing is $1.25/1M tokens from Replicate API.

What API model ID do I use for GPT-5 on OpenAI API?

Use the model ID gpt-5 when calling OpenAI API's API.

Who created GPT-5?

GPT-5 was created by OpenAI as part of the GPT-5 model family.

Is GPT-5 open source?

GPT-5 is not open source; the seed data lists it as proprietary.

Get Started

Model Specs

Released2025-08-07
Context400k
ArchitectureDecoder Only
Knowledge cutoff2024-09

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