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Z-AI has released six distinct GLM models over the past eight months, and every one of them is available on Chat-O today. Here is a complete map of the GLM family: what each model does best, and how to pick the right one for your workflow.
| Model | Released | Context | Tiers Available | Architecture Focus |
|---|---|---|---|---|
| GLM-4.7 | Dec 22, 2025 | 202,752 | Balanced | Stable multi-step reasoning |
| GLM-5 | Feb 11, 2026 | 204,800 | Balanced, Power | General reasoning and coding |
| GLM-5 Turbo | Mar 15, 2026 | 202,752 | Light | Fast inference, agent environments |
| GLM-5.1 | Apr 7, 2026 | 202,752 | Power | Long-horizon coding tasks |
| GLM-5.2 | Jun 16, 2026 | 1,048,576 | Balanced, Power | Agent-optimized, 1M context |
| GLM-5.3 Flash | Aug 26, 2026 | 1.31M | Light, Balanced, Power | Fast everything, any budget |
Released December 22, 2025, GLM-4.7 was Z-AI’s flagship at the time, introducing enhanced programming capabilities and more stable multi-step reasoning. It remains an excellent Balanced-tier choice for everyday work: fast, reliable, and cost-effective.
Best for: Daily coding assistance, stable multi-turn conversations, budget-conscious workloads.
Released February 11, 2026, GLM-5 was Z-AI’s first major leap in reasoning quality, bringing production-grade performance to complex systems design and long-horizon agent workflows. It is still our most popular GLM model thanks to its availability in both Balanced and Power tiers.
Best for: Production code generation, systems design discussions, general reasoning tasks.
Released March 15, 2026, GLM-5 Turbo is the speed specialist of the family, designed for fast inference in agent-driven environments. It trades a little depth for significantly faster response times, and as the only GLM model in the Light tier it is the most economical choice.
Best for: High-volume agent loops, rapid prototyping, cost-sensitive operations.
Released April 7, 2026, GLM-5.1 focused on a single improvement: handling long-horizon tasks better than GLM-5, with significant gains in coding capability across multiple rounds of work. It is Power tier only.
Best for: Complex multi-file coding projects, multi-step refactoring, architectural analysis.
Released June 16, 2026, GLM-5.2 is the previous flagship. Its 1,048,576-token context window and agent-optimized architecture make it the most capable GLM model ever released — until GLM-5.3 Flash arrived with even more context at a fraction of the price.
Best for: Long-horizon agent workflows, whole-codebase analysis, complex multi-step reasoning.
Released August 26, 2026, GLM-5.3 Flash is the newest member of the family and the first GLM model we offer in every tier. It appeared on OpenRouter as a free stealth model called ox alpha, which we used to migrate a full-stack Rails application to Go before Z.AI revealed its identity — read that story here. With a 1.31M-token context window, reliable tool calls, and pricing of $0.075 per million input tokens and $0.25 per million output tokens, its cost-to-intelligence ratio is extraordinary. It is now the default model for a new Chat-O conversation.
Best for: Fast everything at any budget — daily chat, coding assistance, and high-volume agent loops.
| Tier | Available GLM Models | Best For |
|---|---|---|
| Light | GLM-5 Turbo, GLM-5.3 Flash | High volume, fast response, budget priority |
| Balanced | GLM-4.7, GLM-5, GLM-5.2, GLM-5.3 Flash | Daily coding, general reasoning |
| Power | GLM-5, GLM-5.1, GLM-5.2, GLM-5.3 Flash | Deep analysis, complex problems, priority routing |
If you are unsure which GLM model to use, start with GLM-5.3 Flash. It is now the default on Chat-O, and its speed-and-price profile makes it the most versatile starting point. Then follow these upgrade paths as your needs grow:
Each GLM release pushed the frontier in a different direction: GLM-4.7 improved stability, GLM-5 raised absolute quality, GLM-5 Turbo optimized for speed, GLM-5.1 extended coding horizon, GLM-5.2 cracked the million-token barrier, and GLM-5.3 Flash collapsed the cost of all of the above into every tier. Keeping all six available means you can match the model to the task — you would not use GLM-5.2 to summarize a one-paragraph email.
Every GLM model listed here is available in the Chat-O model dropdown right now, and GLM-5.3 Flash is the default for a new conversation. Switch between them between messages. No API keys, no setup, no configuration. Just pick the right tool for the task and go.
Prefer raw API access instead of a chat workspace? We love OpenRouter — it is what we recommend for pure API usage of GLM-5.3 Flash and the rest of the GLM family.
Can I use GLM-5.3 Flash for free on Chat-O?
Yes, for a limited time. Every new account starts with free promotional credits that work in the Light tier, where GLM-5.3 Flash lives. Use them to test the model on real questions before spending anything. When the free credits expire, keep going with our affordable pay-as-you-go subscriptions — you only pay for what you use.
Can I use GLM-5.3 Flash directly from Z.AI?
Yes. As of the writing of this article, Z.AI makes GLM-5.3 Flash available directly, and the open weights are on Hugging Face if you want to run it yourself. One thing to weigh first: with a direct Z.AI account, your data is hosted and processed in China. For a personal experiment that may be fine. For company work or anything under a compliance policy, make sure that arrangement is acceptable to your organization.
Does Chat-O send my data to China?
Chat-O does not use your conversations to train models or sell your information. We apply provider privacy controls and keep conversation history in your Chat-O account for your access. If your organization has contractual or regulatory data-residency requirements, contact us before relying on the service for that workload so we can discuss the fit.
Which GLM model should I start with?
GLM-5.3 Flash. It is the default for a new chat, it runs in every tier, and its cost-to-intelligence ratio means you rarely pay a penalty for picking it. Move up to GLM-5.2 for whole-codebase analysis or GLM-5.1 for marathon coding sessions only when the task demands the extra depth.
Is GLM-5.3 Flash open weight?
Yes. Z.AI publishes the weights on Hugging Face, so you can self-host it if your workflow requires it — unusual at this price point, and one of the reasons we were comfortable making it the Chat-O default. If self-hosting is the plan, OpenRouter is the fastest way to compare it against the rest of the GLM family first.
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