whichllmmodel
Back to Dashboard
Z.ai (Zhipu AI)

GLM-4.5

VS
Z.ai (Zhipu AI)

GLM-5.1

✍️ Analysis by:the whichllmmodel Editorial Team|📅 Updated: June 2026

Decision Recommendation

⚖️ Editorial Verdict: In our analysis, GLM-5.1 is the premium intelligence choice, scoring 58.4% higher on coding benchmarks. However, this accuracy premium comes with a cost overhead: GLM-4.5 is 1.5x cheaper to run. If you are building high-volume, simple chatbots or processing massive amounts of text where budget is critical, GLM-4.5 offers excellent cost savings. For agentic reasoning, code refactoring, or complex logical tasks, the accuracy premium of GLM-5.1 fully justifies the cost.

Model Specs

GLM-4.5

Benchmarks & Scores

Coding (swe-bench-pro)
N/A
Reasoning (gpqa-diamond)
79.9%

Cost & Performance

Cost (per 1M tokens)1.5x cheaper
$1.00Input: $0.60 | Output: $2.20
Speed
N/A
Context Window
131.07k tokens
Model Specs

GLM-5.1

Benchmarks & Scores

Coding (swe-bench-pro)Winner (+)
58.4%
Reasoning (gpqa-diamond)Winner (+6.3%)
86.2%

Cost & Performance

Cost (per 1M tokens)
$1.50Input: $0.98 | Output: $3.08
Speed
N/A
Context WindowLarger
204.8k tokens

Frequently Asked Questions

GLM-4.5 is cheaper than GLM-5.1. GLM-4.5 has a blended cost of $1.00/1M tokens, which is about 1.5x cheaper than GLM-5.1 at $1.50/1M tokens.

Speed metrics are currently unavailable for both models.

GLM-5.1 is better for coding tasks. It scores 58.4% on coding evaluations (swe-bench-pro) compared to GLM-4.5 which scores N/A.

Want to customize weights or add more models?

Open our interactive dashboard where you can adjust your priority levels for speed, budget, or accuracy slider-bars and watch model rankings calculate dynamically.

Customize in Interactive Dashboard