AI Recommendation
Should you use GLM-5.3?
GLM-5.3 is listed for chat workloads and supports a 1.0M context window.
Use it when OpenCode Zen's free tier is enough for evaluation, demos, or light production traffic.
GLM-5.3 Free API on OpenCode Zen
Free API VerifiedFlagship GLM model for long-horizon coding, agents, and complex project delivery
Free APIOpenAI compatibleReasoningTool callingJSON modeReasoning
API Details
Copy-ready connection details
Base URL
https://opencode.ai/zen/v1 Model ID
glm-5.3 API format OpenAI Chat Completions
Technical Details
GLM-5.3 specifications
Context window 1.0M
Max output 131K
Status Online
Family glm
Released Aug 14, 2026
Last updated Aug 14, 2026
Free listing since Sep 19, 2026
Input text
Output text
Capabilities reasoning, tool calling, structured output, temperature control
Open weights Yes
Best for
- Chat
Strengths & Weaknesses
Strengths
- Long context window
- Reasoning mode listed
- Tool calling support
- Structured JSON output
Watch outs
- Vision support is not listed
Benchmark Overview
Benchmark signals for GLM-5.3
Intelligence General reasoning and instruction following
44.9/100 Coding Programming and code generation
74.8/100 Agentic Tool use and multi-step tasks
53.4/100 Speed Observed generation speed
68 tok/s Context Maximum listed context window
1.0M Pricing
GLM-5.3 pricing per 1M tokens
Input $1.4 per 1M tokens
Output $4.4 per 1M tokens
Access Available OpenCode Zen
Availability
GLM-5.3 availability by provider
We only found this GLM-5.3 listing on OpenCode Zen in the current catalog. Use the related models section for nearby alternatives.
| Provider | Model listing | Access | Context | API | Limits |
|---|---|---|---|---|---|
| | GLM-5.3 | Free tier | 1.0M | Native | Varies |
Compare
GLM-5.3 alternatives to consider
| Model | Provider | Context | Access |
|---|---|---|---|
| big-pickle | OpenCode Zen | N/A | Free tier |
| DeepSeek V4 Flash | OpenCode Zen | 1.0M | Check provider |
| MiMo-V2.5 | OpenCode Zen | 1.0M | Free tier |
| Nemotron 3 Ultra 550B A55B | OpenCode Zen | 1.0M | Free tier |
| North Mini Code | OpenCode Zen | 256K | Check provider |
Typical Use Cases
GLM-5.3 use cases
Chat
GLM-5.3 is tagged for chat in this catalog and works with OpenAI-compatible client libraries.
FAQ
GLM-5.3 free API FAQ
Is GLM-5.3 free to use?
GLM-5.3 is listed with free API access on OpenCode Zen, subject to the provider's quota and account policy.
What is the GLM-5.3 model ID?
The model ID shown in this catalog is glm-5.3.
What context window does GLM-5.3 support?
The listed context window is 1.0M tokens with up to 131K output tokens.
More about GLM-5.3
Free GLM-5.3 API.
For API keys, setup steps, and provider-level limits, see the OpenCode Zen provider page.