OpenAI compatible API · Attested · Public status

OpenAI: gpt-oss-20b vs Z.ai: GLM 5.2

gpt-oss-20b vs Z.ai: GLM 5.2: compare current API pricing, context, provider routes, privacy, p50 latency, and OpenAI-compatible access.

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

OpenAI: gpt-oss-20b 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 Z.ai: GLM 5.2 with the lower p50 TTFT.

$0.1785/1MOpenAI: gpt-oss-20b cheapest route

$2.289/1MZ.ai: GLM 5.2 cheapest route

1662 msOpenAI: gpt-oss-20b fastest measured p50 TTFT via together

1147 msZ.ai: GLM 5.2 fastest measured p50 TTFT via friendli

OpenAI: gpt-oss-20bZ.ai: GLM 5.2

Model idopenai/gpt-oss-20bz-ai/glm-5.2

Publisher OpenAI Z.AI

AI IQ IQ 100#70 IQ 120#16

Context131,072 tokens1,048,576 tokens

Provider routes1545

Cheapest route$0.1785/1M$2.289/1M

Privacy posturehas ZDR routehas provider E2EE route

Fastest measured p50 TTFT1662 ms via together1147 ms via friendli

Highest measured throughputnot enough datanot enough data

Recent route uptime range100.00%85.71% to 100.00%

Modes chat chat

OpenAI: gpt-oss-20b routes

Overview15 endpoints
PricingPrompt and completion rates
ProvidersAll serving providers

Z.ai: GLM 5.2 routes

Overview45 endpoints
PricingPrompt and completion rates
BenchmarksTrustedRouter and external sources
ProvidersAll serving providers

Related comparisons

Browse every comparison

MoonshotAI: Kimi K2.6 vs Z.ai: GLM 5.275 combined provider routes
MoonshotAI: Kimi K3 vs Z.ai: GLM 5.275 combined provider routes
OpenAI: gpt-oss-120b vs Z.ai: GLM 5.270 combined provider routes
DeepSeek: DeepSeek V4 Flash 0423 vs Z.ai: GLM 5.269 combined provider routes
DeepSeek: DeepSeek V4 Pro vs Z.ai: GLM 5.269 combined provider routes
Z.ai: GLM 5.1 vs Z.ai: GLM 5.269 combined provider routes
Google: Gemma 4 31B vs Z.ai: GLM 5.268 combined provider routes
MiniMax: MiniMax M3 vs Z.ai: GLM 5.264 combined provider routes

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-oss-20b",
    messages=messages,
)

Questions

Which should I use, OpenAI: gpt-oss-20b or Z.ai: GLM 5.2?

Is OpenAI: gpt-oss-20b or Z.ai: GLM 5.2 cheaper?

The current cheapest TrustedRouter route is $0.1785/1M for OpenAI: gpt-oss-20b and $2.289/1M for Z.ai: GLM 5.2. The comparison uses current catalog prices and updates as provider pricing changes.

Is OpenAI: gpt-oss-20b or Z.ai: GLM 5.2 faster?

Current measured p50 time to first token is 1662 ms for OpenAI: gpt-oss-20b and 1147 ms for Z.ai: GLM 5.2. These are routed probe measurements, not vendor-advertised speeds, and update as new samples arrive.

Can I test OpenAI: gpt-oss-20b and Z.ai: GLM 5.2 with the same API?

Yes. Use the same OpenAI-compatible TrustedRouter base URL and API key, then change only the model id between openai/gpt-oss-20b and z-ai/glm-5.2. This makes side-by-side evals possible without maintaining two provider integrations.