OpenAI compatible API · Attested · Public status

OpenAI: GPT-4o vs Z.ai: GLM 5.2

Compare OpenAI: GPT-4o and Z.ai: GLM 5.2 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 5.2 has the lower cheapest prompt+completion route on TrustedRouter. Z.ai: GLM 5.2 has more provider fallback routes, while Z.ai: GLM 5.2 has the larger context window. Current TrustedRouter probes show OpenAI: GPT-4o with the lower p50 TTFT.

$13.125/1MOpenAI: GPT-4o cheapest route

$3.927/1MZ.ai: GLM 5.2 cheapest route

967 msOpenAI: GPT-4o measured p50 TTFT

1350 msZ.ai: GLM 5.2 measured p50 TTFT

OpenAI: GPT-4oZ.ai: GLM 5.2

Model idopenai/gpt-4oz-ai/glm-5.2

PublisherOpenAIZ.AI

AI IQ IQ # IQ 120#16

Context128,000 tokens1,048,576 tokens

Provider routes543

Cheapest route$13.125/1M$3.927/1M

Privacy posturehas ZDR routehas provider E2EE route

Modes chat chat

OpenAI: GPT-4o routes

Overview5 endpoints
PricingPrompt and completion rates
ProvidersAll serving providers

Z.ai: GLM 5.2 routes

Overview43 endpoints
PricingPrompt and completion rates
BenchmarksTrustedRouter and external sources
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="openai/gpt-4o",
    messages=messages,
)