Free to start

Anthropic: Claude Sonnet 5.5 vs Z.ai: GLM 5.3 Flash

Try both on us. Starter credit covers your first requests, then one key routes Claude Sonnet 5.5 and GLM 5.3 Flash. Switch by changing the model name.

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 published input-plus-output rate, more Credits provider routes, the larger context window and the lower measured p50 time to first token.

$12.66/1MAnthropic: Claude Sonnet 5.5 cheapest route

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

3168 msAnthropic: Claude Sonnet 5.5 fastest measured p50 TTFT via anthropic

1003 msZ.ai: GLM 5.3 Flash fastest measured p50 TTFT via crusoe

The price comparison adds each route's rate for one million input tokens and one million output tokens; your cost depends on your input/output mix. 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.

Anthropic: Claude Sonnet 5.5Z.ai: GLM 5.3 Flash

Model idanthropic/claude-sonnet-5.5z-ai/glm-5.3-flash

Publisher Anthropic Z.AI

AI IQ IQ 137#7 IQ 119#45

Context1,000,000 tokens1,048,576 tokens

Credits provider routes132

Cheapest route$12.66/1M$0.32705/1M

Cached input$0.1055/1M$0.015825/1M to $0.068575/1M

Privacy postureprovider posture varieshas Confidential route (E2EE + ZDR)

Fastest measured p50 TTFT3168 ms via anthropic1003 ms via crusoe

Highest measured throughputnot enough datanot enough data

Recent route uptime range100.00%96.67% to 100.00%

Modes chat messages chat

Anthropic: Claude Sonnet 5.5 routes

Overview1 Credits routes

Z.ai: GLM 5.3 Flash routes

Overview32 Credits routes
PricingInput, cached input, and output rates
ProvidersAll serving providers

Related comparisons

Browse every comparison

Z.ai: GLM 5.3 vs Z.ai: GLM 5.3 Flash65 combined provider routes
Z.ai: GLM 5.2 vs Z.ai: GLM 5.3 Flash64 combined provider routes
MoonshotAI: Kimi K3 vs Z.ai: GLM 5.3 Flash60 combined provider routes
DeepSeek: DeepSeek V4 Flash 0731 vs Z.ai: GLM 5.3 Flash58 combined provider routes
DeepSeek: DeepSeek V4.1 Flash vs Z.ai: GLM 5.3 Flash56 combined provider routes
OpenAI: gpt-oss-120b vs Z.ai: GLM 5.3 Flash56 combined provider routes
Qwen: Qwen3.8 27B vs Z.ai: GLM 5.3 Flash51 combined provider routes
MoonshotAI: Kimi K2.6 vs Z.ai: GLM 5.3 Flash49 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="anthropic/claude-sonnet-5.5",
    messages=messages,
)

Questions

Which should I use, Anthropic: Claude Sonnet 5.5 or Z.ai: GLM 5.3 Flash?

Z.ai: GLM 5.3 Flash has the lower published input-plus-output rate, more Credits provider routes, the larger context window and the lower measured p50 time to first token.

Is Anthropic: Claude Sonnet 5.5 or Z.ai: GLM 5.3 Flash cheaper?

The current cheapest TrustedRouter route is $12.66/1M for Anthropic: Claude Sonnet 5.5 and $0.32705/1M for Z.ai: GLM 5.3 Flash. The comparison uses current catalog prices and updates as provider pricing changes.

Is Anthropic: Claude Sonnet 5.5 or Z.ai: GLM 5.3 Flash faster?

Current measured p50 time to first token is 3168 ms for Anthropic: Claude Sonnet 5.5 and 1003 ms for Z.ai: GLM 5.3 Flash. These are routed probe measurements, not vendor-advertised speeds, and update as new samples arrive.

Can I test Anthropic: Claude Sonnet 5.5 and Z.ai: GLM 5.3 Flash with the same API?

Yes. Use the same OpenAI-compatible TrustedRouter base URL and API key, then change only the model id between anthropic/claude-sonnet-5.5 and z-ai/glm-5.3-flash. This makes side-by-side evals possible without maintaining two provider integrations.