GPT-4.5 vs GPT OSS 120B
Compare GPT-4.5 and GPT OSS 120B, both from OpenAI, context windows of 128K vs 131K, tested across 25 shared challenges. Updated June 2026.
Which is better, GPT-4.5 or GPT OSS 120B?
GPT-4.5 and GPT OSS 120B are both competitive models. GPT-4.5 costs $75/M input tokens vs $0.18/M for GPT OSS 120B. Context windows: 128K vs 131K tokens. Compare their real outputs side by side below.
Key Differences Between GPT-4.5 and GPT OSS 120B
GPT-4.5 is made by openai while GPT OSS 120B is from openai. GPT-4.5 has a 128K token context window compared to GPT OSS 120B's 131K. On pricing, GPT-4.5 costs $75/M input tokens vs $0.18/M for GPT OSS 120B.
Per 1M tokens
GPT OSS 120B is cheaper on both — 417× input, 188× output
No community votes yet. On paper, these are closely matched - try both with your actual task to see which fits your workflow.
GPT OSS 120B is 188x cheaper per token — worth considering if cost matters.
Style Comparison
GPT OSS 120B uses 15.4x more emoji
