Claude Sonnet 5.5 vs GLM 5.2

Practical read: GLM 5.2 costs about a sixth as much and starts answering sooner. One API key runs both.

No card required. Start with 1 million free tokens.

Side by side:

Anthropic: Claude Sonnet 5.5 compared with Z.ai: GLM 5.2
Attribute	Claude Sonnet 5.5 `anthropic/claude-sonnet-5.5`	GLM 5.2 `z-ai/glm-5.2`
Price, 1M in + out	$12.66 Anthropic, cheapest route	$2.30 Engy, cheapest route
Best for		Low cost and speed
Input / output, 1M	$2.11 / $10.55	$0.72 / $1.58
Cached input	$0.1055/1M to $0.11605/1M	$0.131875/1M to $0.773315/1M
Context window	1M 1,000,000 tokens	1.05M 1,048,576 tokens
First token, p50	4.4 s via Amazon Bedrock	0.66 s via FriendliAI
Throughput	Measuring	265 tok/s via Telnyx
AI IQ	IQ 137 #8 on AI IQ	IQ 118 #53 on AI IQ
Provider routes	2 with failover	31 with failover
Privacy	Zero retention route	Confidential E2EE and zero retention route
Recent route uptime range	100.00%	0.00% to 100.00%
Publisher	Anthropic	Z.AI
Modes	chat messages	chat
More detail	Overview Pricing Providers	Overview Pricing Providers Benchmarks

Price adds one million input and one million output tokens on the cheapest route. Prices and speed change: see the monthly reports and run a small eval before you choose a default.

Test both with your agent

Paste this into Claude Code, Cursor or any coding agent.

Compare Claude Sonnet 5.5 and GLM 5.2 in this project through TrustedRouter.

1. Read https://trustedrouter.com/docs/llms.txt
2. Point the OpenAI-compatible client at
   https://api.trustedrouter.com/v1 and read the key from
   TRUSTEDROUTER_API_KEY.
3. Run our eval prompts on anthropic/claude-sonnet-5.5, then on z-ai/glm-5.2.
4. Show me cost, latency and quality side by side before changing the default.

import os
from openai import OpenAI

client = OpenAI(
    base_url="https://api.trustedrouter.com/v1",
    api_key=os.environ["TRUSTEDROUTER_API_KEY"],
)
for model in ("anthropic/claude-sonnet-5.5", "z-ai/glm-5.2"):
    response = client.chat.completions.create(
        model=model,
        messages=[{"role": "user", "content": "What is the capital of France?"}],
    )
    print(model, response.choices[0].message.content)

for model in anthropic/claude-sonnet-5.5 z-ai/glm-5.2; do
  curl https://api.trustedrouter.com/v1/chat/completions \
    -H "Authorization: Bearer $TRUSTEDROUTER_API_KEY" \
    -H "Content-Type: application/json" \
    -d "{\"model\": \"$model\", \"messages\": [{\"role\": \"user\", \"content\": \"What is the capital of France?\"}]}"
done

Your agent will need an API key.

Questions

Which should I use, Anthropic: Claude Sonnet 5.5 or Z.ai: GLM 5.2?

Z.ai: GLM 5.2 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 5.2 cheaper?

The current cheapest TrustedRouter route is $12.66/1M for Anthropic: Claude Sonnet 5.5 and $2.2999/1M for Z.ai: GLM 5.2. The comparison uses current catalog prices and updates as provider pricing changes.

Is Anthropic: Claude Sonnet 5.5 or Z.ai: GLM 5.2 faster?

Current measured p50 time to first token is 4442 ms for Anthropic: Claude Sonnet 5.5 and 659 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 Anthropic: Claude Sonnet 5.5 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 anthropic/claude-sonnet-5.5 and z-ai/glm-5.2. This makes side-by-side evals possible without maintaining two provider integrations.

More comparisons

All comparisons

Try Claude Sonnet 5.5 and GLM 5.2 with one key.

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.

No card required. Start with 1 million free tokens.