GLM 4.5 Air (free) API
About
Build advanced reasoning agents with GLM 4.5 Air (free), a specialized AI model optimized for complex logic and chain-of-thought tasks. This model delivers available completely free of charge, native tool calling support, open weights architecture. Access GLM 4.5 Air (free) via the OpenRouter API with up to 96K output tokens.
Capabilities
Input Modalities
text
Output Modalities
text
Reasoning
Yes
Structured Output
No
Tool Use
Yes
WeightsOpen
Temperature
Adjustable
Attachment
Not Supported
Limits
Context Window
131K
Tokens
Input Limit
131K
Tokens
Max Output
96K
Tokens
Pricing
Standard (per 1M tokens)
Input
Free
Output
Free
Frequently Asked Questions
GLM 4.5 Air (free) by OpenRouter costs Free per 1M input tokens and Free per 1M output tokens.
Model Details
ID
z-ai/glm-4.5-air:free
Provider
OpenRouterFamily
glm-air
Release Date
Jul 28, 2025
Knowledge Cutoff
Apr 1, 2025
API Integration
NPM Package
@openrouter/ai-sdk-provider
Environment Variables
OPENROUTER_API_KEY
API Base URL
https://openrouter.ai/api/v1