Output tokens cost $3.94 per million on GLM 5.2 and $0.55 per million on gpt-oss-20b. Input tokens cost $1.13 per million on GLM 5.2 and $0.11 per million on gpt-oss-20b. Cached input tokens are billed at $0.28 per million on GLM 5.2 and $0.11 per million on gpt-oss-20b. Context lengths are 1,000,000 tokens on GLM 5.2 and 128,000 tokens on gpt-oss-20b. Time to first token (TTFT) measured on AIHubMix is 0.6s on GLM 5.2 and 0.1s on gpt-oss-20b. Measured output throughput is 42.8 tok/s on GLM 5.2 and 2619.0 tok/s on gpt-oss-20b. On the LMArena coding leaderboard GLM 5.2 scores 1505 and gpt-oss-20b scores 1370.
GLM 5.2
gpt-oss-20bGLM-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-oss-20b is a 21-billion parameter open-weight model released by OpenAI under the Apache 2.0 license. Its core feature is a Mixture-of-Experts (MoE) architecture that uses only 3.6B active parameters, enabling low-latency inference and deployment on consumer GPUs. The model also supports fine-tuning, function calling, tool use, and structured outputs.
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.
gpt-oss-20b: $0.55/M output tokens; GLM 5.2: $3.94/M. Use the cost calculator above to estimate your own workload.
GLM 5.2: 1505; gpt-oss-20b: 1370 (LMArena coding leaderboard).
gpt-oss-20b: 0.1s 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-oss-20b accepts 128,000 input tokens. Maximum output per request is 128,000 tokens on GLM 5.2 and 128,000 tokens on gpt-oss-20b.
gpt-oss-20b at 2619.0 tok/s and GLM 5.2 at 42.8 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-oss-20b accepts text 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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