Model Comparison
GLM-4.5-Air
vs. GPT-4.5 (Preview)
Comparing 2 AI models · 12 benchmarks · Z AI, OpenAI
Recommended Pick
Op GPT-4.5 (Preview) 4 metric wins Strongest on: Input price, Output price, TTFT
Lowest Price
GPT-4.5 (Preview)
$0.00/1M input price
Best Reasoning
GLM-4.5-Air
60.3 reasoning score
Blends available reasoning benchmarks
Best for Coding
GLM-4.5-Air
23.8 coding index
Composite Indices
Higher is better; speed and price are normalized
Standard Benchmarks
Only benchmarks with data are shown
Differences That Matter
Price gap
GPT-4.5 (Preview) is ∞x cheaper on input tokens than GLM-4.5-Air.
Reasoning gap
GLM-4.5-Air leads GPT-4.5 (Preview) by 46.7 points on reasoning.
Top-pick rationale
GPT-4.5 (Preview) wins 4 measurable categories, including Input price, Output price, TTFT, Latency.
Response Face-Off
Run one prompt through the selected models and compare response quality with live speed and cost context.
GLM-4.5-Air
Z AI
TTFT
—
Time
—
tok/s
—
Tokens
—
Cost
—
GPT-4.5 (Preview)
OpenAI
TTFT
—
Time
—
tok/s
—
Tokens
—
Cost
—
Which answer was more useful?
Full Comparison
| Metric | Z GLM-4.5-Air | Top Pick Op GPT-4.5 (Preview) |
|---|---|---|
| Pricing per 1M tokens | ||
| Input Cost | $0.17/1M | $0.00/1M |
| Output Cost | $0.98/1M | $0.00/1M |
| Blended (3:1) | $0.37/1M | — |
| Specifications | ||
| Organization | Z AI | OpenAI |
| Release Date | Jul 28, 2025 | Feb 27, 2025 |
| Performance & Speed | ||
| Throughput | 73.9 tok/s | — |
| TTFT | 1501ms | — |
| Latency | 28556ms | — |
| Composite Indices | ||
| Value Score | 100.0 | — |
| Reasoning Score | 60.3 | 13.6 |
| Intelligence | 16.5 | 13.6 |
| Coding | 23.8 | — |
| Math | 80.7 | — |
| Standard Benchmarks | ||
| GPQA | 73.3% | — |
| MMLU Pro | 81.5% | — |
| HLE | 6.8% | — |
| LiveCodeBench | 68.4% | — |
| MATH 500 | 96.5% | — |
| AIME 2025 | 80.7% | — |
| AIME (Original) | 67.3% | — |
| SciCode | 30.6% | — |
| LCR | 43.7% | — |
| IFBench | 37.6% | — |
| TAU-bench v2 | 46.5% | — |
| TerminalBench Hard | 20.5% | — |
Key Takeaways
GPT-4.5 (Preview) offers the best value at $0.00/1M, making it ideal for high-volume applications and cost-conscious projects.
GLM-4.5-Air has the strongest reasoning profile with a 60.3 reasoning score, combining the available reasoning-heavy benchmarks.
GLM-4.5-Air reaches a 23.8 coding index, making it the top choice for software development and code generation tasks.
All models support context windows of ∞+ tokens, suitable for processing lengthy documents and maintaining extended conversations.
When to Choose Each Model
GLM-4.5-Air
- Complex reasoning tasks
- Research & analysis
- Code generation
- Software development
GPT-4.5 (Preview)
- Cost-sensitive applications
- High-volume processing
