Compare GLM 5.2 from Z.AI and GPT-5.2-Codex from OpenAI on key metrics including benchmarks, price, context length, and other model features. Access both models and hundreds of others through the AIHubMix API.
GLM 5.2
GPT-5.2-CodexGLM-5.2 is Z.ai’s flagship model for the era of long-horizon tasks. With a truly usable 1M-token context window, it can handle project-level engineering context, execute long-running tasks more reliably, follow engineering standards more consistently, and complete the full development workflow from requirements to multi-platform deployment in a single task.
GPT-5.2-Codex is an upgraded version of GPT-5.2, optimized for agentic coding tasks in Codex and similar execution environments. The model is specifically enhanced for code generation, modification, refactoring, and automated execution workflows, enabling more efficient participation in multi-step, tool-driven programming processes. GPT-5.2-Codex supports low, medium, high, and xhigh reasoning effort settings, allowing flexible trade-offs between latency, reasoning depth, and token usage depending on task complexity.
Prices are per million tokens. Time to First Token and throughput are rolling averages measured on AIHubMix.
Promotional prices show the discounted rate; see each model page for promotion windows.
Daily traffic served through AIHubMix — how demand for each model is trending.
Measured on real AIHubMix traffic, hourly buckets. Gaps mean no traffic in that hour.
LMArena ratings by capability (Bradley-Terry, commonly called Elo). Higher is better.
Source: LMArena (arena.ai) leaderboard, imported by AIHubMix. Models without published ratings are omitted per chart.
Estimate your monthly bill for the same workload on each model.
Monthly = daily × 30. Discounted rates applied where a promotion is active.
GLM 5.2: $3.94/M output tokens; GPT-5.2-Codex: $14.00/M. Use the cost calculator above to estimate your own workload.
GPT-5.2-Codex: 0.7s time to first token measured on AIHubMix; see the live performance charts above for how each model behaves across the day.
GLM 5.2 accepts 1,000,000 and GPT-5.2-Codex accepts 400,000 input tokens. Maximum output per request is 128,000 tokens on GLM 5.2 and 128,000 tokens on GPT-5.2-Codex.
GPT-5.2-Codex at 81.8 tok/s and GLM 5.2 at 34.8 tok/s, measured as output throughput on AIHubMix — a separate metric from time to first token.
GLM 5.2 accepts text input and supports thinking, tool calling, function calling and structured outputs; GPT-5.2-Codex accepts text and image input and supports thinking, function calling and structured outputs.
Yes. AIHubMix serves every model on this page behind one OpenAI-compatible endpoint, so switching between them is a one-line change to the model field — no second account, key or SDK.
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