Z.ai · Open weights
GLM 4.5 Air (Thinking)
GLM-4.5-Air with thinking mode enabled for enhanced reasoning capabilities. Shows step-by-step thought process.
- Reasoning
- Tools
- Structured output
- Input
- Text
- Output
- Text
- Discovery tier
- Open weights
Pricing
USD per 1M tokens- Input
- $0.13
- Output
- $0.85
- Cache read
- $0.025
Reference prices as published by the model provider. API example
Specifications
- Context window
- 128K
- Max output
- 98.3K
- Average output (7 days)
- 973 tokens
- Longer than 70% of 465 models
Side by side
GLM 4.5 Air (Thinking) compared
Specifications, prices, speed and benchmark scores next to each other. Benchmarks below show every compared model too.
| GLM 4.5 Air (Thinking)Z.aiThis model | GLM 5.3 UncensoredZ.aiRemove | |
|---|---|---|
| Provider | Z.ai | Z.ai |
| Discovery tier | Open weights | Open weights |
| Added | Jan 1, 2024 | Sep 26, 2026 |
| Limits | ||
| Context window | 128K | 1.05MBest |
| Max output | 98.3K | 131.07KBest |
| Average output | 973 tokens | 1.1K tokens |
| Pricing, USD per 1M tokens | ||
| Input | $0.13Best | $1.25 |
| Output | $0.85Best | $2.25 |
| Cache read | $0.025Best | $0.30 |
| Performance | ||
| Throughput | — | 37.0 tok/s |
| Time to first token | — | 7.6 s |
| Request success (24h) | 100.0%Best | 98.8% |
| Benchmark indexes | ||
| Intelligence Index | 11.1 | — |
| Math Index | 80.7 | — |
| Capabilities | ||
| Reasoning | Yes | Yes |
| Tools | Yes | Yes |
| Structured output | Yes | No |
| Reasoning effort | — | low, high, max |
Public evaluations
Benchmarks
Independent evaluation results, with how each score ranks among the models in the Noumen catalog.
- GLM 4.5 Air (Thinking)
- GLM 5.3 Uncensored
Intelligence Index
- GLM 4.5 Air (Thinking)11.1
- GLM 5.3 Uncensored—
GLM 4.5 Air (Thinking): Better than 23% of 326 scored models
Indexes
Math Index
Composite of the math evaluations
- GLM 4.5 Air (Thinking): 80.7
- GLM 5.3 Uncensored: —
Document reasoning
AA-LCRv1.1
Reasoning across long documents
- GLM 4.5 Air (Thinking): 46.7%
- GLM 5.3 Uncensored: —
Reasoning and knowledge
Humanity’s Last Exam
Expert-level questions across academic fields
- GLM 4.5 Air (Thinking): 7.0%
- GLM 5.3 Uncensored: —
GPQA Diamond
Graduate-level science questions
- GLM 4.5 Air (Thinking): 73.3%
- GLM 5.3 Uncensored: —
MMLU-Pro
Multi-subject knowledge and reasoning
- GLM 4.5 Air (Thinking): 81.5%
- GLM 5.3 Uncensored: —
IFBench
Following precise output instructions
- GLM 4.5 Air (Thinking): 37.6%
- GLM 5.3 Uncensored: —
Coding
LiveCodeBench
Recent competitive programming problems
- GLM 4.5 Air (Thinking): 68.4%
- GLM 5.3 Uncensored: —
Math
AIME 2025
Competition mathematics, 2025 problems
- GLM 4.5 Air (Thinking): 80.7%
- GLM 5.3 Uncensored: —
AIME
Competition mathematics
- GLM 4.5 Air (Thinking): 67.3%
- GLM 5.3 Uncensored: —
MATH-500
Competition math problems
- GLM 4.5 Air (Thinking): 96.5%
- GLM 5.3 Uncensored: —
Legacy evaluations
Terminal-Bench Hard
Earlier terminal task suite
- GLM 4.5 Air (Thinking): 20.5%
- GLM 5.3 Uncensored: —
τ²-Bench Telecom
Tool use in a customer-support simulation
- GLM 4.5 Air (Thinking): 46.5%
- GLM 5.3 Uncensored: —
AA-LCR (unversioned)
Long-context reasoning, earlier grading
- GLM 4.5 Air (Thinking): 46.7%
- GLM 5.3 Uncensored: —
Scores from Artificial Analysis, updated Oct 26, 2026. Artificial Analysis
- GLM 4.5 Air (Thinking)
- GLM 5.3 Uncensored
| Leaderboard | GLM 4.5 Air (Thinking) | GLM 5.3 Uncensored |
|---|---|---|
| Usage Share | Not in top 20 | #8 · 4.8% |
Ranks among Noumen catalog models on Usage leaderboards. Only top-20 placements are listed.
Live routing data
Performance and reliability
Recent averages across requests routed for this model. Your own speed depends on prompt length, reasoning effort and load.
- Prompt cache hits
- 36.0%
- About $0.0922 per 1M input tokens with caching
- Request success (24h)
- 100.0%
- Reliable
Cache hits are the share of input tokens recently served from a prompt cache across all requests. They are not a forecast of your own hit rate.
- Healthy (98% or more)
- Degraded (90–98%)
- Down (under 90%)
- No requests
Developers
Use it through the API
Noumen’s API is OpenAI-compatible: any Chat Completions client works with a base URL and a key.
curl https://www.noumen.xyz/api/v1/chat/completions \
-H "Authorization: Bearer $NOUMEN_API_KEY" \
-H "Content-Type: application/json" \
-d '{
"model": "z-ai/GLM-4.5-Air:thinking",
"messages": [{ "role": "user", "content": "Explain this stack trace." }]
}'import os
from openai import OpenAI
client = OpenAI(base_url="https://www.noumen.xyz/api/v1", api_key=os.environ["NOUMEN_API_KEY"])
reply = client.chat.completions.create(
model="z-ai/GLM-4.5-Air:thinking",
messages=[{"role": "user", "content": "Explain this stack trace."}],
)
print(reply.choices[0].message.content)Z.ai
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