GPT-4.5 vs Quasar Alpha
Compare GPT-4.5 by OpenAI against Quasar Alpha by OpenRouter, context windows of 128K vs 1.0M, tested across 6 shared challenges. Updated April 2026.
Which is better, GPT-4.5 or Quasar Alpha?
GPT-4.5 and Quasar Alpha are both competitive models. Context windows: 128K vs 1000K tokens. Compare their real outputs side by side below.
Key Differences Between GPT-4.5 and Quasar Alpha
GPT-4.5 is made by openai while Quasar Alpha is from openrouter. GPT-4.5 has a 128K token context window compared to Quasar Alpha's 1000K.
Our Verdict
GPT-4.5
Quasar Alpha
No community votes yet. On paper, these are closely matched - try both with your actual task to see which fits your workflow.
Too close to call
vsAsk them anything yourself
Some models write identically. You are paying for the brand.
178 models fingerprinted across 32 writing dimensions. Free research.
Model Similarity Index
185x
price gap between models that write identically
178
models
12
clone pairs
32
dimensions
Devstral M / S
95.7%
Qwen3 Coder / Flash
95.6%
GPT-5.4 / Mini
93.3%
279 AI models invented the same fake scientist.
We read every word. 250 models. 2.14 million words. This is what we found.
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