GPT-6 Astra

Text & chatNewAvailable
by OpenAIModel ID: gpt-6-astra

OpenAI's most capable model, built for the hardest end-to-end work. Reasoning, text and image input, function calling and tool use, 1,050,000-token context window and up to 128,000 output tokens. Knowledge cutoff April 30, 2026.

Price · 1M in / out
US$12.00 / US$60.00
Context
1 050 000 tokens
Max. output
128 000 tokens
Input → output
Text → Text
Developer
OpenAI
Updated
24 September 2026
01

Playground

Try GPT-6 Astra

Chat

US$12.00/1M in
Try GPT-6 Astra

Send a message. The answer arrives in full once the model is done (no streaming).

System prompt
Max. answer length (tokens)

This run

at most US$0.0615 · 6.15 credits reserved

Billed by the tokens actually used; the unused part of the reservation is refunded.

For accounts without a purchase: runs above 2 credits need a top-up.

New here?

10 free credits (US$0.10) when you sign up with Google

Usable 24 hours after sign-up, up to 5 runs per day and at most 2 credits per run. Other sign-in methods start without credits.

02

About GPT-6 Astra

TL;DRAs of 24 September 2026

GPT-6 Astra is a model by OpenAI in the Text & chat category. On Railwail, GPT-6 Astra costs US$12.00 per 1M input tokens and US$60.00 per 1M output tokens. The context window holds 1 050 000 tokens, and one response can be up to 128 000 tokens long.

03

Pricing

Prices in US dollars. Usage is charged from prepaid credits.
InputUS$12.00 / 1M tokens
OutputUS$60.00 / 1M tokens
Input (prompts over 272 000 tokens)US$24.00 / 1M tokens
Output (prompts over 272 000 tokens)US$90.00 / 1M tokens
  • Billed by the tokens each request actually uses.
  • 1 credit = US$0.01

Cost calculator

Price calculator

/ req.
/ req.

Total

US$4.20

420 credits

Per request

US$0.042 · 4.2 credits

Each request is rounded up to 0.01 credits.

04

API

Call GPT-6 Astra with your Railwail API key. Use this model ID in the request:
curl https://railwail.com/api/v1/chat/completions \
  -H "Authorization: Bearer $RAILWAIL_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "gpt-6-astra",
    "messages": [
      {
        "role": "user",
        "content": "Explain what a vector database is in two sentences."
      }
    ],
    "max_tokens": 1024
  }'
Set your key as RAILWAIL_API_KEYCreate API key
05

Specifications

Model ID
gpt-6-astra
Developer
OpenAI
Category
Text & chat
Input
Text
Output
Text
Context window
1 050 000 tokens
Max. output
128 000 tokens
Billing
By usage (tokens or GPU time)
Catalog entry updated
24 September 2026

Tags

  • openai
  • gpt-6
  • flagship
  • reasoning
  • vision
  • tools
06

Use cases

07

Frequently asked questions

What is GPT-6 Astra?

GPT-6 Astra is a model by OpenAI in the Text & chat category. On Railwail you can call it with an API key through the Railwail API.

How much does GPT-6 Astra cost on Railwail?

On Railwail, GPT-6 Astra costs US$12.00 per 1M input tokens and US$60.00 per 1M output tokens. You are charged for what each request actually uses. Usage is paid from prepaid credits; 1 credit equals US$0.01.

What is the context window of GPT-6 Astra?

The context window of GPT-6 Astra holds 1 050 000 tokens. One response can be up to 128 000 tokens long.

How fast is GPT-6 Astra?

There are not enough measured runs of GPT-6 Astra on Railwail yet to state a run time. It depends on the input, the settings and the load at the provider.

Is GPT-6 Astra better than Claude Fable 5.1?

That depends on the task. GPT-6 Astra (OpenAI) and Claude Fable 5.1 (Anthropic) are both models in the Text & chat category. The comparison page shows their prices and specifications side by side.

Compare GPT-6 Astra and Claude Fable 5.1

How do I use GPT-6 Astra through the API?

Create a Railwail API key and send your request with the model ID gpt-6-astra. Code examples for curl, Python and JavaScript are in the API section of this page.

08

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Use GPT-6 Astra via the API

One API key for every model on Railwail. Usage is charged from prepaid credits, 1 credit = US$0.01.