GLM-5.3 API

GLM-5.3 is Zhipu AI flagship MoE LLM with a 1M-token context window, built for advanced text generation and deep reasoning.

Modalities: TextText
In / Out price: $1.4/$4.4per 1M
Context window: 1.02M tokens
Released: Aug 17, 2026

GLM-5.3 overview

GLM-5.3 by Zhipu AI

GLM-5.3 is Zhipu AI's newest flagship model, offering a 1M-token context window with deep, tunable reasoning and full parallel tool-calling support for building advanced agents.

GLM-5.3 specs

Model ID: zhipu/glm-5.3
Developer: Zhipu AI
Context window: 1,024,000 tokens
Max output: 131,072 tokens
Input: Text
Output: Text
API: OpenAI-compatible, base URL https://api.aimlapi.com/v1

What Is GLM-5.3 API?

GLM-5.3 is Zhipu AI's newest flagship large language model, built for advanced text generation and deep reasoning. It carries forward the GLM series' full 1M-token context window and adds native, parallel tool/function calling with strict JSON schema output, making it a solid base for agentic applications that need to hold a lot of context and act on it reliably.

Technical Reference

Developer	Zhipu AI
Model ID	zhipu/glm-5.3
Release Date	August 17, 2026
Context Window	1,024,000 tokens (~1M)
Max Output Tokens	131,072
Modalities	Text (input and output)
Capabilities	Reasoning, parallel tool/function calling, streaming, structured (JSON schema) output

What GLM-5.3 Brings to the Table

The headline spec is the context window: at just over 1,000,000 tokens, GLM-5.3 can hold large documents, long conversation histories, or sizeable codebases in a single request without needing to chunk or summarize first.

Deep, controllable reasoning

GLM-5.3 supports chain-of-thought style reasoning for complex, multi-step problems, alongside faster inference for simpler queries, letting you balance latency and depth depending on the task.

Parallel tool calling with structured output

The model can call multiple tools/functions in a single turn and return responses that strictly conform to a provided JSON schema, which is useful for building reliable agents and structured data pipelines rather than free-form text you have to parse yourself.

Streaming support

Responses can be streamed token-by-token, keeping latency low for chat-style interfaces even on long-context requests.

Use cases

Software engineering and coding workflows are a documented fit for GLM 5.3, including complex software engineering, repo-scale coding, and agentic development tasks.

Long-horizon agent tasks are another stated use case, with the model described as suited to multi-step, tool-driven workflows that need to stay coherent over long contexts.

Cybersecurity work is also explicitly mentioned as a target use case, including “emergent cyber capabilities” and cybersecurity scenarios.

Structured generation and analysis are documented uses as well, including structured outputs, analysis, and long-form text handling in development workflows.

Capabilities

Reasoning
Structured outputs
Streaming
Function calling

GLM-5.3 benchmarks by Artificial Analysis

See how GLM-5.3 compares in intelligence, generation speed, cost per task and latency. Data retrieved Nov 3, 2026.

Intelligence#19 / 5031.7Index v5.0 Speed#124 / 21989.0Output tokens / second Cost per task#39 / 44$5.01USD / benchmark task Latency#108 / 2161.43Seconds to first token

Benchmark results

Compare 12 models available on AI/ML API across 5 independent benchmarks.

Humanity's Last Exam

Expert-written questions across academic subjects.

GLM-5.3 API pricing

GLM-5.3 pricing in US dollars
Usage	Price	Unit
Input	$1.4	1M tokens
Output	$4.4	1M tokens
Cached input	$0.26	1M tokens

Prices from the AI/ML API price list, checked on Nov 4, 2026.

GLM-5.3 vs other models: token prices

AI/ML API input and output rates for 5 models, per million tokens.

AI/ML API model prices in USD per million tokens
Model	Input	Output
GLM-5.3	$1.4	$4.4
GLM-5.3-Flash	$0.15	$0.5
GLM 5.3 FlashX	$0.37	$1.25
GLM 5.2	$1.4	$4.4
GLM 5.2 Fast Preview	$3.5	$11

How to use the GLM-5.3 API

View docs

Build with your agent

Give your agent the model details, code and documentation.

1Get your API key

Create API key

export AIMLAPI_KEY="8f2b4c7d9a1e6b3f…"

2Make your first request

curl 'https://api.aimlapi.com/v1/chat/completions' \
  -H "Authorization: Bearer $AIMLAPI_KEY" \
  -H 'Content-Type: application/json' \
  -d '{
  "model": "zhipu/glm-5.3",
  "messages": [
    {
      "role": "user",
      "content": "Write a haiku about the ocean."
    }
  ]
}'

import os
import requests

headers = {
    "Authorization": f"Bearer {os.environ['AIMLAPI_KEY']}",
    "Content-Type": "application/json",
}
payload = {
    "model": "zhipu/glm-5.3",
    "messages": [
        {
            "role": "user",
            "content": "Write a haiku about the ocean."
        }
    ]
}

response = requests.post("https://api.aimlapi.com/v1/chat/completions", headers=headers, json=payload, timeout=120)
response.raise_for_status()
print(response.json())

const response = await fetch("https://api.aimlapi.com/v1/chat/completions", {
  method: "POST",
  headers: {
    Authorization: `Bearer ${process.env.AIMLAPI_KEY}`,
    "Content-Type": "application/json",
  },
  body: JSON.stringify({
    "model": "zhipu/glm-5.3",
    "messages": [
      {
        "role": "user",
        "content": "Write a haiku about the ocean."
      }
    ]
  }),
});

if (!response.ok) throw new Error(`HTTP ${response.status}`);
console.log(await response.json());

All posts

GLM-5.3 FAQ

What is the context window of GLM-5.3?

GLM-5.3 has a 1,024,000 tokens context window and can return up to 131,072 tokens.

What inputs and outputs does GLM-5.3 support?

GLM-5.3 takes text as input and returns text.

What is the model ID for GLM-5.3?

Use zhipu/glm-5.3 as the model id. Requests go to https://api.aimlapi.com/v1/chat/completions.

When was GLM-5.3 released?

GLM-5.3 became available on August 17, 2026.

How much does GLM-5.3 cost?

GLM-5.3 costs $1.4 input and $4.4 output per 1M tokens on AI/ML API, billed as you go with no subscription.

Does GLM-5.3 support streaming?

Yes, GLM-5.3 can stream responses as they are generated.

Who created GLM-5.3?

GLM-5.3 was built by Zhipu AI.

Start building with GLM-5.3

Get API key

GLM-5.3 API

zhipu/glm-5.3

Build with your agent

Give your agent the model details, code and documentation.

1Get your API key

Create API key

export AIMLAPI_KEY="8f2b4c7d9a1e6b3f…"

2Make your first request

curl 'https://api.aimlapi.com/v1/chat/completions' \
  -H "Authorization: Bearer $AIMLAPI_KEY" \
  -H 'Content-Type: application/json' \
  -d '{
  "model": "zhipu/glm-5.3",
  "messages": [
    {
      "role": "user",
      "content": "Write a haiku about the ocean."
    }
  ]
}'

import os
import requests

headers = {
    "Authorization": f"Bearer {os.environ['AIMLAPI_KEY']}",
    "Content-Type": "application/json",
}
payload = {
    "model": "zhipu/glm-5.3",
    "messages": [
        {
            "role": "user",
            "content": "Write a haiku about the ocean."
        }
    ]
}

response = requests.post("https://api.aimlapi.com/v1/chat/completions", headers=headers, json=payload, timeout=120)
response.raise_for_status()
print(response.json())

const response = await fetch("https://api.aimlapi.com/v1/chat/completions", {
  method: "POST",
  headers: {
    Authorization: `Bearer ${process.env.AIMLAPI_KEY}`,
    "Content-Type": "application/json",
  },
  body: JSON.stringify({
    "model": "zhipu/glm-5.3",
    "messages": [
      {
        "role": "user",
        "content": "Write a haiku about the ocean."
      }
    ]
  }),
});

if (!response.ok) throw new Error(`HTTP ${response.status}`);
console.log(await response.json());

Docs for AI agents Plain-text index · llms.txt API documentation API reference and examples

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GLM-5.3 API

GLM-5.3 overview

GLM-5.3 by Zhipu AI

GLM-5.3 specs

What Is GLM-5.3 API?

Technical Reference

What GLM-5.3 Brings to the Table

Deep, controllable reasoning

Parallel tool calling with structured output

Streaming support

Use cases

Capabilities

GLM-5.3 benchmarks by Artificial Analysis

Intelligence

Speed

Cost per task

Benchmark results

Humanity's Last Exam

GPQA Diamond

Terminal-Bench 4.0

AA-LCR

SciCode

GLM-5.3 API pricing

GLM-5.3 vs other models: token prices

How to use the GLM-5.3 API

Build with your agent

1Get your API key

2Make your first request

Related articles

GLM-5.3 FAQ

Start building with GLM-5.3

GLM-5.3 API

Build with your agent

1Get your API key

2Make your first request

GLM-5.3 API

GLM-5.3 overview

GLM-5.3 by Zhipu AI

GLM-5.3 specs

What Is GLM-5.3 API?

Technical Reference

What GLM-5.3 Brings to the Table

Deep, controllable reasoning

Parallel tool calling with structured output

Streaming support

Use cases

Capabilities

Intelligence

Speed

Cost per task

Benchmark results

Humanity's Last Exam

GPQA Diamond

Terminal-Bench 4.0

AA-LCR

SciCode

GLM-5.3 API pricing

GLM-5.3 vs other models: token prices

How to use the GLM-5.3 API

Build with your agent

1Get your API key

2Make your first request

Models similar to GLM-5.3

GLM 5.3 FlashX

GLM-5.3-Flash

GLM 5.2 Fast Preview

ERNIE 5.0

Qwen3.5 Omni Plus

Mistral Large 4

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GLM-5.3 FAQ

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