GLM-5.3 Prime
z-ai/glm-5.3-prime
Guide only
- Released
- Sep 23, 2026
- Context window
- 1M
- Max output
- 131K
- In / out per 1M
- $2.80 / $8.80
- Inputs
- Text
z-ai/glm-5.3-prime
Model guide · September 2026
GLM-5.3 Prime: GLM-5.3, accelerated
GLM-5.3 Prime is the high-speed variant of GLM-5.3. It inherits the flagship's capabilities and, according to Z.ai, delivers 1.5–2× the output throughput through inference acceleration. It is available through APIs only.
GLM-5.3 Prime is not available in our chat. The closest models you can try here for free are GLM-5.3 Flash and GLM-5.3.
§ 01Datasheet
GLM-5.3 Prime specifications
| OpenRouter ID | z-ai/glm-5.3-prime |
|---|---|
| Developer | Z.ai |
| Released | Sep 23, 2026 |
| Context window | 1,000,000 tokens |
| Max output | 131,072 tokens |
| Input price | $2.80 per 1M tokens |
| Output price | $8.80 per 1M tokens |
| Inputs | Text |
| Open weights | No |
| Parameters | Not published |
| Licence | Not published |
| Free chat here | Guide only |
Source: OpenRouter model list and the official Hugging Face model cards.
§ 02Overview
What GLM-5.3 Prime is
Same model quality, more speed
GLM-5.3 Prime was listed on OpenRouter on 23 September 2026. Its description says it inherits the full capabilities of GLM-5.3 while producing 1.5 to 2 times more output tokens per second thanks to inference acceleration. It is not a different model in the sense of new training; it is GLM-5.3 served faster.
Speed matters most in agent loops and interactive coding tools, where a model may generate hundreds of thousands of tokens over a session. Halving the wait between steps can change how usable an agent feels.
Specifications and price
Prime accepts text and returns text. OpenRouter lists a 1,000,000-token context window and a maximum output of 131,072 tokens per request — a shorter output limit than standard GLM-5.3. Supported parameters include reasoning, reasoning_effort, tools and structured response formats.
The speed has a price: $2.80 per million input tokens and $8.80 per million output tokens, against $0.079 and $1.40 for standard GLM-5.3. There are no public weights for GLM-5.3 Prime.
When Prime is worth it
Pick Prime when a human is waiting on every step and GLM-5.3's quality is what you need — for example, a coding assistant inside an IDE or a live agent demo. For batch jobs, overnight agents or anything where cost matters, standard GLM-5.3 delivers the same capability at a small fraction of the price.
Prime is not available in our free chat. You can get a feel for its quality by trying standard GLM-5.3 here; the answers come from the same model.
- Use Prime for latency-sensitive, interactive GLM-5.3 workloads.
- Use standard GLM-5.3 for cost-sensitive or batch work.
- Use GLM-5.3 Flash or FlashX when you also need image input.
§ 03Strengths
Where GLM-5.3 Prime is strong
GLM-5.3 capability
Inherits the flagship's full abilities in coding, reasoning and long agent tasks.
1.5–2× throughput
Inference acceleration produces output noticeably faster than standard GLM-5.3.
Large context
A 1M-token window for big codebases and long documents.
Agent-ready API
Supports tool calling, reasoning controls and structured outputs.
§ 04How to try
Three ways to use GLM-5.3 Prime
Preview quality free
Try standard GLM-5.3 in our chat; Prime runs the same model faster.
Call z-ai/glm-5.3-prime
Use OpenRouter with any OpenAI-compatible client, exactly like other GLM models.
Measure the gain
Benchmark latency on your own prompts and decide if the speed justifies the higher price.
§ 05Family
The rest of the GLM-5 family
Every model page uses the same datasheet, so you can compare them at a glance.
| Model | Released | Context window | In / out per 1M | Free chat here |
|---|---|---|---|---|
| GLM-5 | Feb 11, 2026 | 205K | $1 / $3.20 | — |
| GLM-5-Turbo | Mar 15, 2026 | 203K | $1.20 / $4 | — |
| GLM-5V-Turbo | Apr 1, 2026 | 203K | $1.20 / $4 | — |
| GLM-5.1 | Apr 7, 2026 | 205K | $1.40 / $4.40 | — |
| GLM-5.2 | Jun 16, 2026 | 1.05M | $0.0341 / $7 | — |
| GLM-5.3 | Aug 18, 2026 | 1.05M | $0.079 / $1.40 | In our chat |
| GLM-5.3 Flash | Aug 26, 2026 | 1.05M | $0.0052 / $0.1985 | In our chat |
| GLM-5.3 FlashX | Sep 18, 2026 | 1.05M | $0.37 / $1.25 | — |
| GLM-5.3 Prime | Sep 23, 2026 | 1M | $2.80 / $8.80 | — |
§ 06FAQ
GLM-5.3 Prime questions
Q01Is GLM-5.3 Prime smarter than GLM-5.3?
No. It inherits GLM-5.3's capabilities; the difference is 1.5–2× higher output throughput, according to Z.ai.
Q02How much does GLM-5.3 Prime cost?
On OpenRouter it costs $2.80 per million input tokens and $8.80 per million output tokens.
Q03Does GLM-5.3 Prime have open weights?
No public weights are listed for GLM-5.3 Prime. The open GLM-5.3 weights correspond to the standard model.
Q04Can I use GLM-5.3 Prime on glm5.org?
Not directly. Our free chat runs GLM-5.3 and GLM-5.3 Flash.
§ 07Related
Keep reading
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