Model garden On request

Apertus 8B 2509

This model runs as a dedicated deployment on large GPUs and isn't in the shared playground by default. Get in touch and we'll set it up for you.

1. Model Summary 2. How to use 3. Evaluation 4. Training 5. Limitations 6. Legal Aspects

swiss-ai/Apertus-8B-2509 On request
text->text · swiss-ai · EU-hosted
8.1B
Parameters
66K
Context window
24GB
Minimum VRAM
POST /api/v1/chat/completions On request

Specifications

Parameters 8.1B
Context window 65,536 tokens
Minimum VRAM 24 GB
Architecture ApertusForCausalLM (vLLM)
License apache-2.0
Modality text->text
Released September 2025
Publisher swiss-ai ↗

Pricing

€0.05
Input (per 1M tokens)
€0.12
Output (per 1M tokens)

Shared EU router, pay-per-token, scale-to-zero. Dedicated GPU deployments are billed hourly, see pricing.

Not available on the shared router. Pricing on request as a dedicated GPU deployment.

Call it now

Drop-in replacement for OpenAI: change only the base URL and API key. The Anthropic format (/v1/messages) is supported too.

curl https://hostyourai.com/api/v1/chat/completions \
  -H "Authorization: Bearer hyai-..." \
  -H "Content-Type: application/json" \
  -d '{
    "model": "swiss-ai/Apertus-8B-2509",
    "messages": [{"role": "user", "content": "Hello!"}]
  }'

Frequently asked questions

Can I run Apertus 8B 2509 in the EU?

Yes. HostYourAI runs Apertus 8B 2509 on GPUs in European datacenters via vLLM. Prompts and outputs never leave the EU and there is no US cloud provider in the chain.

Is hosting Apertus 8B 2509 GDPR-compliant?

Yes. All processing happens inside the EU, a Data Processing Agreement (DPA) is available and the subprocessor list is public. Open-source weights also mean: no training on your data.

How much does Apertus 8B 2509 cost?

Via the shared EU router you pay €0.05 per million input tokens and €0.12 per million output tokens, with no fixed costs. For high volume or isolation you can also run Apertus 8B 2509 as a dedicated hourly GPU instance.

Is the API OpenAI-compatible?

Yes. You use the standard OpenAI SDKs with a custom base URL (https://hostyourai.com/api/v1). The Anthropic Messages API is supported as a drop-in as well.

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