OpenAI compatible API · Attested · Public status

Z.ai: GLM 5.1 vs GLM 5.2 Fast on Fireworks

Compare Z.ai: GLM 5.1 and GLM 5.2 Fast on Fireworks by providers, context, price, and TrustedRouter route support.

Verify gateway

Onebase URL to migrate

100sof models and routes

0prompt or output logs. Always.

Compare routesProviders, price, context, and policy posture in one view.

Use auto when uptime mattersKeep a primary model and let fallback handle provider failures.

Same API shapeUse the OpenAI client and set the model you want.

Practical read

Z.ai: GLM 5.1 has the lower cheapest prompt+completion route on TrustedRouter. Z.ai: GLM 5.1 has more provider fallback routes, while GLM 5.2 Fast on Fireworks has the larger context window. Current TrustedRouter probes show GLM 5.2 Fast on Fireworks with the lower p50 TTFT.

$4.263/1MZ.ai: GLM 5.1 cheapest route

$9.135/1MGLM 5.2 Fast on Fireworks cheapest route

1437 msZ.ai: GLM 5.1 measured p50 TTFT

730 msGLM 5.2 Fast on Fireworks measured p50 TTFT

Z.ai: GLM 5.1GLM 5.2 Fast on Fireworks

Model idz-ai/glm-5.1z-ai/glm-5.2-fast

PublisherZ.AIZ.AI

AI IQ IQ 114#32 —

Context204,800 tokens1,048,576 tokens

Provider routes246

Cheapest route$4.263/1M$9.135/1M

Privacy posturehas confidential-compute routeprovider posture varies

Modes chat chat

Z.ai: GLM 5.1 routes

Overview24 endpoints
PricingPrompt and completion rates
BenchmarksTrustedRouter and external sources
ProvidersAll serving providers

GLM 5.2 Fast on Fireworks routes

Overview6 endpoints
PricingPrompt and completion rates
ProvidersAll serving providers

Production choice

Pick a default model. Keep fallback enabled.

TrustedRouter is useful when you know the model you want, but still need provider rollover, budget limits, usage records, and a prompt path you can verify.

OpenAI clientPython

client = OpenAI(
    base_url="https://api.trustedrouter.com/v1",
    api_key="sk-tr-v1-..."
)

response = client.chat.completions.create(
    model="z-ai/glm-5.1",
    messages=messages,
)