Decision Models s1-pro-5 (EU) vs DeepSeek V4.1 Flash

Practical read: Decision Models s1-pro-5 (EU) costs less. DeepSeek V4.1 Flash reads more context. One API key runs both.

No card required. Start with 1 million free tokens.

Side by side:

Decision Models s1-pro-5 (EU) compared with DeepSeek: DeepSeek V4.1 Flash
Attribute	Decision Models s1-pro-5 (EU) `decisionmodelsio-eu/s1-pro-5`	DeepSeek V4.1 Flash `deepseek/deepseek-v4.1-flash`
Price, 1M in + out	$0.089 Decision Models (EU), cheapest route	$0.16 Engy, cheapest route
Best for	Low cost	Long documents
Input / output, 1M	$0.089 / $0	$0.032 / $0.13
Cached input	Not published	$0.01/1M to $0.1899/1M
Context window	8K 8,192 tokens	1.05M 1,048,576 tokens
First token, p50	Measuring	0.71 s via Together
AI IQ	Unrated	IQ 126 #24 on AI IQ
Provider routes	1	21 with failover
Privacy	Varies by provider	Confidential E2EE and zero retention route
Recent route uptime range	not enough data	80.00% to 100.00%
Publisher	decisionmodelsio-eu	DeepSeek
Modes	decide	chat decide
More detail	Overview	Overview Pricing Providers

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.

Try it

Decision models: the API, the models, the numbers

curl https://api.trustedrouter.com/api/alpha/decide \
  -H "Authorization: Bearer sk-tr-v1-..." \
  -H "Content-Type: application/json" \
  -d '{
    "model": "decisionmodelsio-eu/s1-pro-5",
    "state": "Customer: I was charged twice for order A-1.",
    "questions": {
      "refund": {"type": "boolean", "instructions": "Is a refund requested?"}
    }
  }'

Your agent will need an API key.

Questions

Which should I use, Decision Models s1-pro-5 (EU) or DeepSeek: DeepSeek V4.1 Flash?

Decision Models s1-pro-5 (EU) has the lower published input-plus-output rate. DeepSeek V4.1 Flash has more Credits provider routes and the larger context window. There is not enough recent probe data to compare speed.

Is Decision Models s1-pro-5 (EU) or DeepSeek: DeepSeek V4.1 Flash cheaper?

The current cheapest TrustedRouter route is $0.08862/1M for Decision Models s1-pro-5 (EU) and $0.15825/1M for DeepSeek: DeepSeek V4.1 Flash. The comparison uses current catalog prices and updates as provider pricing changes.

Is Decision Models s1-pro-5 (EU) or DeepSeek: DeepSeek V4.1 Flash faster?

Current measured p50 time to first token is not enough data for Decision Models s1-pro-5 (EU) and 711 ms for DeepSeek: DeepSeek V4.1 Flash. These are routed probe measurements, not vendor-advertised speeds, and update as new samples arrive.

Can I test Decision Models s1-pro-5 (EU) and DeepSeek: DeepSeek V4.1 Flash with the same API?

Yes. Both take the same request on POST /api/alpha/decide, with the same TrustedRouter base URL and API key, so a side-by-side eval changes only the model id between decisionmodelsio-eu/s1-pro-5 and deepseek/deepseek-v4.1-flash. Decision Models s1-pro-5 (EU) does not take chat requests.

More comparisons

All comparisons

Try Decision Models s1-pro-5 (EU) and DeepSeek V4.1 Flash 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.