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GPT-6 Astra vs Union Alpha

Compare GPT-6 Astra from OpenAI and Union Alpha from Stealth on key metrics including benchmarks, price, context length, and other model features. Access both models and hundreds of others through the OpenRouter API.

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AI Model Comparison

Favicon for openai
GPT-6 Astra
Favicon for stealth
Union Alpha
Favicon for openai
GPT-6 Astra
Favicon for stealth
Union Alpha

Overview

GPT-6 Astra
Author
OpenAI
Union Alpha
Author
Stealth
GPT-6 Astra
Context length
1.05Mtokens
Union Alpha
Context length
262Ktokens
GPT-6 Astra
Reasoning
Union Alpha
Reasoning
GPT-6 Astra
Input modalities
Union Alpha
Input modalities
GPT-6 Astra
Output modalities
Union Alpha
Output modalities

GPT-6 Astra vs Union Alpha: side-by-side summary

GPT-6 Astra and Union Alpha are available through the OpenRouter API, so switching between them takes a model slug change rather than a new integration.

GPT-6 Astra, from OpenAI, has a 1,050,000-token context window and is priced at $10/M tokens input, $50/M tokens output on OpenRouter.

Union Alpha, from Stealth, has a 262,144-token context window and is free to use on OpenRouter.

Context window
  • GPT-6 Astra: 1,050,000 tokens
  • Union Alpha: 262,144 tokens
Price
  • GPT-6 Astra: $10/M tokens input, $50/M tokens output
  • Union Alpha: Free
Provided by
  • GPT-6 Astra: OpenAI
  • Union Alpha: Stealth
  • GPT-6 Astra model details, providers and pricing
  • Union Alpha model details, providers and pricing