GLM-5.3-Flash Is Live on APIMaster.ai at $0.15 per Million Input Tokens

What is GLM-5.3-Flash?

GLM-5.3-Flash is a frontier multimodal model from Z.ai. Unlike a text model with vision added later, it was pretrained across text and visual data as one system. Z.ai says its multimodal pretraining corpus contains 30 trillion tokens.

The model uses 320 billion total parameters but activates about 18 billion per token. It is also the first open-source frontier model that Z.ai describes as combining sparse attention with linear attention. Compared with the full GLM-5.3, Z.ai reports 3.01× less attention computation and a 4.44× smaller KV cache, while using only 45 layers.

Specification	GLM-5.3-Flash
Model ID on APIMaster	glm-5.3-flash
Architecture	Native multimodal Mixture of Experts
Total / active parameters	320B / 18B
Layers	45
Context window	1 million tokens
Inputs	Text, images, video, and files
Core API features	Thinking, streaming, function calling, context caching, structured output
APIMaster input price	$0.15 per 1M tokens

GLM-5.3-Flash features and advantages

1. Native multimodal visual coding

GLM-5.3-Flash can inspect a reference interface, understand its layout and visual state, generate code, observe the rendered result, and iterate. Z.ai highlights workflows that turn screenshots, web pages, URLs, and screen recordings into applications.

This closed loop is useful for:

• front-end implementation from screenshots or design references;
• interactive web apps and games;
• Blender scene construction and editing;
• browser-use and computer-use agents;
• CAD and other visually grounded engineering tasks.

2. Efficient hybrid attention for long contexts

Long-running agents repeatedly reread repositories, tool output, screenshots, and conversation history. GLM-5.3-Flash's hybrid sparse and linear attention architecture targets this bottleneck directly. The 1M-token context window can hold large codebases, lengthy research material, multi-file documents, or extensive agent traces in one request.

The architectural savings do not guarantee the same latency on every provider or prompt. Measure time to first token, generation speed, cache hits, and task completion on your own workload.

3. Strong coding and agent performance

Z.ai reports a 63.4 score on DeepSWE v1.1, up from 46.2 for GLM-5.2, and 48.8 on AutomationBench, up from 26.2. On Z.ai Code Bench at maximum reasoning effort, it reports 29.0, close to Claude Opus 4.8's 29.5 in the same table.

These are vendor-reported benchmark results, not a guarantee for every production task. Their practical signal is that GLM-5.3-Flash is designed for multi-step software engineering, tool use, and autonomous workflows rather than only short chat responses.

4. Professional document and research workflows

The model can work across PPTX, PDF, DOCX, and XLSX files. Z.ai demonstrates office-document generation, financial research, visual report analysis, and presentation creation. Native multimodality helps when a document mixes prose, tables, charts, screenshots, and scanned pages.

5. Images, video, files, and structured tools

GLM-5.3-Flash accepts multiple images through image_url, and its documented capabilities also include video and file understanding. It supports function calling, structured output, context caching, thinking mode, streaming, and tool streaming—useful building blocks for production agents.

GLM-5.3-Flash pricing on APIMaster.ai

GLM-5.3-Flash is available in the APIMaster model marketplace and active channel data now.

Token type	APIMaster base price per 1M tokens
Input	$0.15
Output	$0.50
Cached input	$0.03

Data point: Processing 10 million uncached input tokens and generating 1 million output tokens costs $2.00 at the base token price. If all 10 million input tokens are cache reads, the same token volume costs $0.80.

This is a dated price snapshot from August 27, 2026. The marketplace shows current route data; final wallet charges can reflect the selected account group or route multiplier. Check the live price before committing a large workload.

When should you use GLM-5.3-Flash?

• Visual coding: Rebuild or modify interfaces from screenshots, recordings, or rendered output.
• Coding agents: Repository analysis, implementation, debugging, testing, and tool-heavy engineering.
• Long-context analysis: Large repositories, research sets, contracts, reports, and long agent histories.
• Document automation: Understand and create presentations, spreadsheets, PDFs, and word-processing files.
• Multimodal research: Analyze images, charts, video, files, and text in one workflow.
• Computer-use agents: Browser, desktop, Blender, game, and CAD interactions grounded in visual feedback.
• High-volume workloads: Use the Flash tier when both capability and token economics matter.

How to Buy GLM-5.3-Flash?

1. Create an APIMaster account.
2. Add pay-as-you-go credit, starting from $1.
3. Open the model marketplace and select GLM 5.3 Flash.
4. Create an API key in the APIMaster console.
5. Send requests with the model ID glm-5.3-flash.

from openai import OpenAI

client = OpenAI(
    api_key="YOUR_APIMASTER_KEY",
    base_url="https://apimaster.ai/v1",
)

response = client.chat.completions.create(
    model="glm-5.3-flash",
    messages=[
        {
            "role": "user",
            "content": "Review this architecture and propose a tested implementation plan.",
        }
    ],
    temperature=1,
    top_p=0.95,
    extra_body={
        "reasoning_effort": "max",
        "thinking": {"type": "enabled", "clear_thinking": False},
    },
)

print(response.choices[0].message.content)

Z.ai recommends temperature=1, top_p=0.95, maximum reasoning effort, and preserving thinking history for multi-turn tasks. For streaming workflows, enable both response streaming and tool streaming where supported. Start with a representative evaluation set before moving production traffic.

Why use GLM-5.3-Flash through APIMaster.ai?

1. Input costs only $0.15 per million tokens

The low base input price makes large contexts, repeated agent steps, and multimodal production pipelines easier to budget. Cache reads at $0.03 per million tokens can further reduce the cost of reused prompts and context.

2. One OpenAI-compatible API for many model families

Use one endpoint and key for GLM, Claude, GPT, DeepSeek, Qwen, Gemini, Kimi, and other models. Teams can compare models or build fallbacks without maintaining a separate provider integration for every family.

3. Transparent live channel data

APIMaster exposes route price, availability, uptime, and channel information in the marketplace. You can evaluate the active route instead of sending production traffic through an opaque model name.

4. Model verification tools

The free AI model fingerprint tester helps developers inspect whether a route behaves like the model it claims to provide. APIMaster combines model testing with ongoing route monitoring.

5. Pay as you go from $1

There is no subscription commitment. Fund a small evaluation, compare quality and total task cost, then scale the workloads where GLM-5.3-Flash performs best.

6. A practical multi-model console

Manage keys, review usage, compare routes, and switch model families from one console. Available payment methods include credit cards, Alipay, WeChat Pay, and USDT.

Start building with GLM-5.3-Flash

GLM-5.3-Flash combines native multimodal understanding, efficient long-context attention, visual coding, professional workflows, and agent capabilities at a low current price. APIMaster makes it available now through an OpenAI-compatible API at $0.15 per million input tokens.

Register for APIMaster · Compare GLM-5.3-Flash routes · Test model identity

FAQ

Is GLM-5.3-Flash available on APIMaster.ai?
Yes. It is live in APIMaster's channel data and model marketplace under the exact model ID glm-5.3-flash.

How much does GLM-5.3-Flash cost?
The APIMaster base token price is $0.15/M input, $0.50/M output, and $0.03/M cache reads. Account-group or route multipliers can affect the final wallet charge.

Does GLM-5.3-Flash support a one-million-token context?
Yes. Z.ai documents a 1M-token context window.

Is GLM-5.3-Flash multimodal?
Yes. It is a native multimodal model supporting text, images, video, and files. Exact request formats can depend on the active endpoint and route.

Can GLM-5.3-Flash generate apps from screenshots?
Yes. Z.ai presents visual coding as a core capability, including workflows based on screenshots, pages, URLs, and screen recordings.

Can I use the OpenAI SDK?
Yes. Set the SDK base URL to https://apimaster.ai/v1, use an APIMaster API key, and send model="glm-5.3-flash".

Should I trust benchmark scores as production guarantees?
No. The published scores are vendor-reported reference points. Evaluate accuracy, tool behavior, latency, and total task cost using your own prompts and data.

Sources and further reading

• Z.ai — official GLM-5.3-Flash guide — z.ai: approximately 25.2M monthly visits, Similarweb July 2026 estimate; docs.z.ai has no standalone estimate
• APIMaster live marketplace and model fingerprint tester — apimaster.ai: under 10K monthly visits / no stable public Similarweb estimate