OpenAI compatible API · Attested · Public status

Z.ai: GLM 5.3 Flash vs GLM 5.1

Z.ai: GLM 5.3 Flash vs GLM 5.1: 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

Monthly evidence

Z.ai: GLM 5.3 Flash has the lower cheapest prompt+completion route on TrustedRouter. Z.ai: GLM 5.3 Flash has more provider fallback routes, while Z.ai: GLM 5.3 Flash has the larger context window. Probe-backed speed data is shown when enough recent samples exist.

$0.32705/1MZ.ai: GLM 5.3 Flash cheapest route

$6.119/1MGLM 5.1 cheapest route

1284 msZ.ai: GLM 5.3 Flash fastest measured p50 TTFT via friendli

not enough dataGLM 5.1 fastest measured p50 TTFT

Prices and live route measurements can change. Use the monthly reports when you need a stable evidence window, then run a small task-specific eval before choosing a production default.

Z.ai: GLM 5.3 FlashGLM 5.1

Model idz-ai/glm-5.3-flashzai-org/GLM-5.1

Publisher Z.AI Nebius Token Factory

AI IQ IQ 121#24 IQ 114#43

Context1,048,576 tokens204,800 tokens

Credits provider routes201

Cheapest route$0.32705/1M$6.119/1M

Cached input$0.015825/1M to $0.1055/1MNot published

Privacy posturehas provider E2EE routehas ZDR route

Fastest measured p50 TTFT1284 ms via friendlinot enough data

Highest measured throughputnot enough datanot enough data

Recent route uptime range0.00% to 100.00%100.00%

Modes chat chat

Z.ai: GLM 5.3 Flash routes

Overview20 Credits routes
PricingInput, cached input, and output rates
ProvidersAll serving providers

GLM 5.1 routes

Overview1 Credits routes

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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-5.3-flash",
    messages=messages,
)

Questions

Which should I use, Z.ai: GLM 5.3 Flash or GLM 5.1?

Is Z.ai: GLM 5.3 Flash or GLM 5.1 cheaper?

The current cheapest TrustedRouter route is $0.32705/1M for Z.ai: GLM 5.3 Flash and $6.119/1M for GLM 5.1. The comparison uses current catalog prices and updates as provider pricing changes.

Is Z.ai: GLM 5.3 Flash or GLM 5.1 faster?

Current measured p50 time to first token is 1284 ms for Z.ai: GLM 5.3 Flash and not enough data for GLM 5.1. These are routed probe measurements, not vendor-advertised speeds, and update as new samples arrive.

Can I test Z.ai: GLM 5.3 Flash and GLM 5.1 with the same API?

Yes. Use the same OpenAI-compatible TrustedRouter base URL and API key, then change only the model id between z-ai/glm-5.3-flash and zai-org/GLM-5.1. This makes side-by-side evals possible without maintaining two provider integrations.