GLM 5.3 FlashX

Name: Z.ai GLM 5.3 FlashX
Price: 0.37 USD
Availability: InStock
Author: Z.ai

z-ai/glm-5.3-flashx

GLM-5.3-FlashX is the high-speed tier of Z.ai's GLM-5.3-Flash, documented together with Flash and delivering inference speeds of up to 200 tokens per second. It shares Flash's native multimodal design and hybrid sparse-plus-linear attention, with image, video and file input, always-on reasoning, tool calling and structured output. Pick it over standard Flash for latency-sensitive coding agents, GUI and browser tasks, and interactive chat.

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Input price: $0.37USD / 1M tokens
Output price: $1.25USD / 1M tokens
Context window: 1M
Max output: 131.1K

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1M context131.1K max outputVision

Input$0.37/MOutput$1.25/MCache read$0.09/M

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Model card

Specifications

Pricing

Input: $0.37 / 1M tokens
Output: $1.25 / 1M tokens
Cache read: $0.09 / 1M tokens

Context & modalities

Context window: 1,048,576 tokens
Max output: 131,072 tokens
Input: Text, image
Output: Text

Capabilities

Chat: Supported
Vision: Supported
Reasoning: Supported
Structured output: Supported
Function calling: Supported
Audio input: Not supported

Access

Provider: Z.ai
Model ID: z-ai/glm-5.3-flashx
Execution: sync
Base URL: https://api.sandbase.ai
API: Chat Completions API
Endpoint: /v1/chat/completions

Start building

Send your first request

OpenAI-compatible endpoint with unified authentication and usage tracking.

Production API

Chat Completions API endpoint

https://api.sandbase.ai/v1/chat/completions

Model ID

z-ai/glm-5.3-flashx

# The quoted heredoc keeps Unicode and shell metacharacters unchanged.
result=$(curl --fail-with-body --silent \
  -X POST "https://api.sandbase.ai/v1/chat/completions" \
  -H "Authorization: Bearer $SANDBASE_API_KEY" \
  -H "Content-Type: application/json" \
  --data-binary @- <<'SANDBASE_JSON'
{
  "model": "z-ai/glm-5.3-flashx",
  "messages": [
    {
      "role": "user",
      "content": "Hello"
    }
  ],
  "max_tokens": 2048
}
SANDBASE_JSON
)
printf '%s\n' "$result"

Choose your model

Compare models

All language models

Model	Context	Input / 1M	Output / 1M	Released
GLM 5.3 FlashXThis model `Z.ai`	1M	$0.37	$1.25	Sep 18, 2026
GLM 5.5 `Z.ai`	—	Coming soon	Coming soon	Coming soon
GLM 5.3 Flash `Z.ai`	1M	$0.15	$0.50	Aug 26, 2026
GLM 5.3 `Z.ai`	1M	$1.40	$4.40	Aug 18, 2026
GLM 5.2 `Z.ai`	1M	$1.40	$4.40	Jun 16, 2026
GLM 4.5 Air `Z.ai`	128K	$0.20	$1.10	Jul 25, 2025

Questions

FAQ

How do I call Z.ai GLM 5.3 FlashX through SandBase?

Create a SandBase API key, then send requests with the model ID "z-ai/glm-5.3-flashx" to Chat Completions API (/v1/chat/completions) at https://api.sandbase.ai. The request examples on this page show the exact payload.

How much does Z.ai GLM 5.3 FlashX cost?

$0.37 per 1M input tokens and $1.25 per 1M output tokens, billed per request from your SandBase balance. Discounts, when available, are shown in the pricing on this page.

What is the context window of Z.ai GLM 5.3 FlashX?

1M tokens of context, with up to 131.1K output tokens per response.

Which features does Z.ai GLM 5.3 FlashX support?

Z.ai GLM 5.3 FlashX supports vision (image input), reasoning, function calling, structured output. See Specifications above for the full list.

Do I need a separate Z.ai account?

No. One SandBase API key and balance gives you access to Z.ai GLM 5.3 FlashX and the other models in the catalog; you do not need to sign up with Z.ai separately.