Doubleword
    Multimodal
    Reasoning
    1.0M Context
    FP8
    Z.ai
    Open Weights

    GLM-5.3-Flash

    A fast, multimodal reasoning model built for coding, tool use, and long-running agentic workflows.

    Quantization

    FP8

    320B MoE · 18B active

    Context Window

    1.0M

    Tokens

    Intelligence

    57

    AA Index

    Released

    Aug 2026

    26 Aug 2026

    About

    Frontier agentic quality, Flash-tier economics

    GLM-5.3-Flash is Z.ai's natively multimodal model for coding, reasoning and agentic workflows. It has 320 billion total parameters with 18 billion active per token, combining sparse and linear attention for efficient long-context processing.

    Trained on a 30-trillion-token multimodal corpus, it improves on GLM-5.2 across coding, tool-use and general capability benchmarks while requiring substantially less serving compute — which is why it lands at a fraction of the price of comparable closed frontier models.

    SWE
    Agent
    Tools
    Vision
    Plan
    Long

    320B MoE · 18B active per token

    Use Cases

    Best for long-running, tool-heavy agents

    Agentic Workflows

    Built for long-running agents: sustained planning, tool orchestration and recovery across hundreds of steps.

    Software Engineering

    Improves on GLM-5.2 across coding benchmarks — multi-file edits, repo-scale refactors and iterative debugging.

    Multimodal Understanding

    Natively multimodal: screenshots, diagrams, dashboards and documents alongside text in the same request.

    Long-Context Analysis

    Sparse plus linear attention keeps 1M-token context efficient for large codebases and document sets.

    Also strong on complex reasoning and multimodal document analysis.

    Pricing

    Flexible Pricing Tiers

    Choose the optimal balance of speed and cost for your workflow. Prices are per 1M tokens.

    Tier Input / 1M tokens Output / 1M tokens
    Batch $0.08 $0.25
    Async $0.11 $0.38
    Realtime $0.15 $0.50

    Context window natively supported up to 1,048,576 tokens. Custom pricing available for bulk discounts and large workloads — reach out to hello@doubleword.ai.

    Quickstart

    Start Building in Minutes

    GLM-5.3-Flash is accessible via OpenAI-compatible endpoints. Default sampling: temperature=1.0, top_p=0.95.

    Python
    from openai import OpenAI
    
    client = OpenAI(
        api_key="your-api-key-here",
        base_url="https://api.doubleword.ai/v1"
    )
    
    # Multimodal, long-running agentic task
    response = client.chat.completions.create(
        model="zai-org/GLM-5.3-Flash",
        messages=[
            {"role": "user", "content": "Trace this stack trace screenshot back to the failing module and patch it."}
        ],
        temperature=1.0,
        top_p=0.95,
    )
    
    print(response.choices[0].message.content)

    💡 Pro Tip

    Route long-running agent steps through the async tier and bulk evals through batch — same model, same API, up to 47% off the realtime rate. See the docs for the batch job format.

    Ready to deploy GLM-5.3-Flash?