glm-5.3 API pricing

glm-5.3 on InferSpeed: $0.84 input, $2.64 output, $0.156 cache read per 1M tokens, 40% below the official list price. OpenAI- and Anthropic-compatible API, pay per token.

Price (USD per 1M tokens)

40% below the official list price.

Endpoints

Authentication: Authorization: Bearer $INFERSPEED_API_KEY (x-api-key also works).

FAQ

How much does the glm-5.3 API cost?

InferSpeed charges $0.84 per 1M input tokens, $2.64 per 1M output tokens and $0.156 per 1M cache-read tokens (USD), billed per token from a prepaid balance. The official list price is $1.40 input / $4.40 output, so this is 40% below the official list price.

Which APIs can I call glm-5.3 with?

The price list names these APIs for glm-5.3: OpenAI Chat Completions (POST https://api.inferspeed.ai/v1/chat/completions) and Anthropic Messages (POST https://api.inferspeed.ai/v1/messages). Authentication: Authorization: Bearer $INFERSPEED_API_KEY (x-api-key also works).

Which API key do I need for glm-5.3?

One API key calls every live model, glm-5.3 included: create a key at https://inferspeed.ai/keys and name the model in the request. Each request is billed at the price of the model that served it.

How do I call glm-5.3?

Set the model explicitly in the request:

curl https://api.inferspeed.ai/v1/chat/completions \
  -H "Authorization: Bearer $INFERSPEED_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "glm-5.3",
    "messages": [{"role": "user", "content": "Say hello in one sentence."}]
  }'

curl https://api.inferspeed.ai/v1/messages \
  -H "x-api-key: $INFERSPEED_API_KEY" \
  -H "anthropic-version: 2023-06-01" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "glm-5.3",
    "max_tokens": 512,
    "messages": [{"role": "user", "content": "Say hello in one sentence."}]
  }'

What happens if I request a model my key cannot call?

It is routed to an available model instead of failing: agent default names such as claude-* and gpt-* go to glm-5.3 (kimi-k3 on a Kimi key). The model field and the X-Served-Model header name the model that served the request (the name you sent is in X-Model-Routed-From), and you are billed at that model's price. Send X-Model-Strict: 1 to get an error instead.

What are the context window and maximum output of glm-5.3?

Measured on glm-5.3: at least 324,955 prompt tokens are accepted, and the maximum output is 131,072 tokens (max_tokens above this returns 400; reasoning tokens count toward it).

More

Setup for Claude Code, Codex CLI, OpenCode and SDKs: /developers.md. All models and prices: /model-plaza. Prices as JSON: /api/v1/public/pricing.