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Mercury 2.5 vs Union Alpha

Compare Mercury 2.5 from inception 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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Mercury 2.5 vs Union Alpha: side-by-side summary

Mercury 2.5 and Union Alpha are available through the OpenRouter API, so switching between them takes a model slug change rather than a new integration.

Mercury 2.5, from inception, has a 260,000-token context window and is priced at $0.04/M tokens input, $0.15/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
  • Mercury 2.5: 260,000 tokens
  • Union Alpha: 262,144 tokens
Price
  • Mercury 2.5: $0.04/M tokens input, $0.15/M tokens output
  • Union Alpha: Free
Provided by
  • Mercury 2.5: inception
  • Union Alpha: Stealth
Favicon for inception
Mercury 2.5
Favicon for stealth
Union Alpha
Favicon for inception
Mercury 2.5
Favicon for stealth
Union Alpha

Overview

Mercury 2.5
Author
inception
Union Alpha
Author
Stealth
Mercury 2.5
Context length
260Ktokens
Union Alpha
Context length
262Ktokens
Mercury 2.5
Reasoning
Union Alpha
Reasoning
Mercury 2.5
Input modalities
Union Alpha
Input modalities
Mercury 2.5
Output modalities
Union Alpha
Output modalities
model details, providers and pricing
model details, providers and pricing
Mercury 2.5
Union Alpha