# GLM-5.1 (Z.ai) — API pricing and providers

> General GLM. Model id `zai/glm-5.1`. Text model by Z.ai.

- Page: https://infro.io/models/zai/glm-5.1
- Vendor: Z.ai (https://infro.io/models/zai)
- Modality: Text
- Endpoint through INFRO: `POST /v1/chat/completions` at https://api.infro.io/v1
- List rate: $1.40 per 1M input tokens and $4.40 per 1M output tokens, with cached input at $0.26 per 1M tokens
- Rates checked: 2026-10-05

Rates are Z.ai's published list price: what the customer's own provider account bills, not an INFRO charge. INFRO is a BYOK control plane; it charges a software subscription and adds 0% to model spend.

## Providers that serve it

| Provider | Model id sent |
| --- | --- |
| OpenRouter | `zai/glm-5.1` |
| Z.ai (GLM) | `glm-5.1` |

## Questions

### How much does the GLM-5.1 API cost?

Z.ai's published list rate for GLM-5.1 is $1.40 per 1M input tokens and $4.40 per 1M output tokens, with cached input at $0.26 per 1M tokens (checked 2026-10-05). The provider account you connect bills you at the rate on that account, so a negotiated rate replaces the list rate. INFRO adds 0% to model spend.

### Which providers serve GLM-5.1?

In INFRO's provider registry, GLM-5.1 can be served by OpenRouter and Z.ai (GLM). You connect your own account with any of them, and INFRO routes and fails over between the ones you connect.

### What is the GLM-5.1 model ID?

Request it from INFRO as "zai/glm-5.1". INFRO sends each provider its own id: OpenRouter "zai/glm-5.1", Z.ai (GLM) "glm-5.1".

### How do I call GLM-5.1 through an OpenAI-compatible API?

Point an OpenAI SDK, or any HTTP client, at https://api.infro.io/v1 with an INFRO gateway key and send model "zai/glm-5.1" to POST /v1/chat/completions. INFRO runs the request on a provider account you connected and returns the provider's response with an estimated cost.

### Does INFRO mark up GLM-5.1 usage?

No. Z.ai or the provider you connect bills model usage to your own account. INFRO charges a software subscription for routing, failover, observability, budgets and policy, and takes 0% of model spend.