Hydro-powered, ethically trained, open source LLM: Apertus 1.5
I hadn't realized they updated this model last month! You can use it here.
Apertus 1.5 70B is Switzerland's latest fully open multilingual large language model developed by the Swiss AI Initiative. It is designed to advance transparent, compliant, and high-performance AI while remaining fully open throughout the entire training pipeline.
- Swiss AI Initiative : Developed by the Swiss AI Initiative to provide a fully open, transparent, and compliant foundation model.
- Fully Open : Open model weights, open training data, complete training recipes, and publicly documented training methodology.
- Massively Multilingual – Native support for 1,811 languages, enabling broad multilingual understanding and generation.
- Compliance First – Trained using fully compliant datasets while respecting retrospective opt-out requests and reducing memorization through the Goldfish loss methodology.
- Long Context – Supports context windows of up to 262,144 tokens, enabling large document analysis and extended conversations.
- Tool Calling Support – Supports agentic workflows and tool use when deployed with compatible inference frameworks such as recent versions of vLLM.
- Open Deployment Ecosystem – Compatible with Transformers, vLLM, SGLang, MLX and GGUF deployment formats.












