GLM-4.5 vs GPT-5.1 Codex High: Specs & Benchmark Comparison

CharacteristicGLM-4.5GPT-5.1 Codex High
CompanyZhipu AIOpenAI
Release DateJuly 27, 2025November 11, 2025
Parameters355B
MultimodalNoYes
Context (input)131K400K
Context (output)98K128K
Input Price / 1M$0.60$1.25
Output Price / 1M$2.20$10.00
Average Score0.81.0

Verdict

GPT-5.1 Codex High leads in 2 out of 4 comparison categories.

Overall Performance

Both models show comparable average scores: GLM-4.5 — 0.8, GPT-5.1 Codex High — 1.0.

API Cost

GLM-4.5 is 4.0x cheaper: input $0.60/1M vs $1.25/1M tokens.

Context Window

GPT-5.1 Codex High supports a larger context: 400K vs 131K tokens.

Recency

GPT-5.1 Codex High is newer: released 11/11/2025 vs 7/27/2025.

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Related Comparisons

The GLM-4.5 and GPT-5.1 Codex High comparison is updated for 2026. Data includes benchmark results, API pricing, context window size and other specifications. For more detailed information, visit the GLM-4.5 or GPT-5.1 Codex High page. See also the complete list of AI model comparisons.