Compare / head-to-head

GLM-5vsGPT-5.1-Codex

GLM-5 leads 3 of 3 shared benchmarks. GLM-5 is 2.7x cheaper per token. GPT-5.1-Codex has the larger context window (400K tokens).

Benchmarks from cited public sources; pricing from official pages; status from official provider feeds.

Shared benchmarks
3 – 0
GLM-5 leads
Cheaper per token
GLM-5
2.7x cheaper, input + output
Larger context
GPT-5.1-Codex
400K tokens
Providers
2 providers
Z.ai · OpenAI
GLM-5
Z.ai
text
Context
200K
Max out
131K
Input /1M
$1 ↗
Output /1M
$3.2 ↗
Cached /1M
$0.2
Scores
21 · 8 core
GPT-5.1-Codex
OpenAI · released 2025-11-13
textvision
Context
400K
Max out
128K
Input /1M
$1.25 ↗
Output /1M
$10 ↗
Cached /1M
$0.125
Scores
4 · 2 core
Quality

Benchmark matrix

BenchmarkGLM-5GPT-5.1-CodexΔEdge
Reported by both · 3
SWE-bench Verified77.8% ↗73.7% ↗+4.1 ptGLM-5
LMArena WebDev (LMArena)1434 ↗1337.1 ↗+96.9GLM-5
Terminal-Bench 2.056.2% ↗52.8% ↗+3.4 ptGLM-5
Only GLM-5 reports · 14
GPQA Diamond87.8% ↗epoch runnot reported——
AIME 202596.7% ↗matharena ⚠not reported——
AIME 202696.7% ↗matharena ⚠not reported——
LMArena Elo1446.3 ↗not reported——
Chess Puzzles (Epoch AI run)10% ↗epoch runnot reported——
OTIS Mock AIME 2024-2025 (Epoch AI run)80% ↗epoch runnot reported——
SimpleBench (SimpleBench)53.2% ↗not reported——
SWE-bench Verified (Epoch AI run)72.1% ↗epoch runnot reported——
tau2-bench Airline (Sierra)82.5% ↗not reported——
tau2-bench Banking Knowledge (Sierra)9.8% ↗not reported——
tau2-bench Retail (Sierra)73.7% ↗not reported——
tau2-bench Telecom (Sierra)86.8% ↗not reported——
Vending-Bench 2 (Andon Labs)4432.12 ↗not reported——
WeirdML (Håvard Tveit Ihle)48.2% ↗not reported——
Only GPT-5.1-Codex reports · 1
SWE-Lancer IC SWEnot reported66.3% ↗——
Scores tagged "epoch" or "matharena" are independent runs, used only where the lab has not published its own; ⚠ marks rows MathArena flags as released after the competition. Higher is better on every row. Δ is GLM-5 minus GPT-5.1-Codex in the benchmark's own unit. "Not reported" means the lab has not published that figure; it is not a zero. ↗ opens the source.
Specs & pricing

Side by side

SpecGLM-5GPT-5.1-CodexEdge
Context window200K tokens400K tokensGPT-5.1-Codex
Max output131K tokens128K tokensGLM-5
Input price / 1M$1 ↗$1.25 ↗GLM-5
Output price / 1M$3.2 ↗$10 ↗GLM-5
Cached input / 1M$0.2 ↗$0.125 ↗GPT-5.1-Codex
Input + output / 1M
Lower is cheaper. List prices; batch, tool and regional fees excluded.
$4.2$11.25GLM-5
Modalitiestexttext · visionGPT-5.1-Codex
Released—2025-11-13—
Cited benchmark scores214—
Reliability

Provider status

All providers →
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Which one wins on your data?

Public benchmarks are a starting point. Run GLM-5 and GPT-5.1-Codex on your own prompts with Respan evals, or route to either through one gateway key with automatic failover.