GPT-5.1-Codex vs o3 Mini
Compare GPT-5.1-Codex and o3 Mini, both from OpenAI, context windows of 400K vs 64K, tested across 53 shared challenges. Updated April 2026.
Which is better, GPT-5.1-Codex or o3 Mini?
GPT-5.1-Codex and o3 Mini are both competitive models. GPT-5.1-Codex costs $1.25/M input tokens vs $1.1/M for o3 Mini. Context windows: 400K vs 64K tokens. Compare their real outputs side by side below.
Key Differences Between GPT-5.1-Codex and o3 Mini
GPT-5.1-Codex is made by openai while o3 Mini is from openai. GPT-5.1-Codex has a 400K token context window compared to o3 Mini's 64K. On pricing, GPT-5.1-Codex costs $1.25/M input tokens vs $1.1/M for o3 Mini.
No community votes yet. On paper, GPT-5.1-Codex has the edge — bigger model tier, newer, bigger context window.
Style Comparison
GPT-5.1-Codex uses 2.0x more lists
vsAsk them anything yourself
Some models write identically. You are paying for the brand.
178 models fingerprinted across 32 writing dimensions. Free research.
185x
price gap between models that write identically
178
models
12
clone pairs
32
dimensions
279 AI models invented the same fake scientist.
We read every word. 250 models. 2.14 million words. This is what we found.
