Apertus

Developed by the Swiss AI Initiative as a collaborative effort between EPFL, ETH Zurich, and CSCS. Open weights, open data, open science.

[Apertus @apertusllm]

Available now! #Apertus 1.5 — 8B & 70B models with multimodal text/image/audio input, 4x longer context window, optional thinking mode, improved tool use, all built transparently and responsibly. 3.2M+ downloads 🚀 #OpenSourceLLM Details+Links+Open roles: https://t.co/OmYc3pGZ5D

[Imanol Schlag @ImanolSchlag]

Hey 👋 Apertus 1.5 is now available to the public on https://t.co/m3lAHGhxod! 😍

Chat with it here: https://t.co/0ej6voZTBB

Try out the image capabilities! I'd be curious what people think before sharing detailed benchmark results :)

[Hanna Yukhymenko @a_yukh]

Hot open-source summer season has gotten to Switzerland 🇨🇭⛰️

Our team at Swiss AI Initiative is happy to release Apertus 1.5 - a multimodal and reasoning update to our first v1 version!

The new version builds a foundation for future regular open model development at scale🧵

[Imanol Schlag @ImanolSchlag]

Today we are releasing Apertus 1.5 8B and 70B, a continued pretraining of our Apertus 1.0 models, which have passed 3.2M downloads in the community. 🧵

[Hanna Yukhymenko @a_yukh]

After escaping European heat with 30+ hrs delay and missing luggage I am finally in San Diego attending @aclmeeting! 🇺🇸🌴#ACL2026

I will be presenting our work on the multilingual benchmark translation from @INSAITinstitute 🇺🇦🇧🇬
📍Poster Session E, July 6th 11.00-12.30

Also check out @apertusllm poster, presented by the greatest @agromanou, to know more about the biggest fully open multilingual models 🇨🇭
📍Poster Session F, July 7th 9.00-10.30

[Apertus @apertusllm]

Three new model weights: 0.5B, 1.5B, 4B are available using new quantization and distillation techniques. Download #Apertus 1.1, read the ICML workshop report, try a new demo - all just a tap away in our latest blog post: https://t.co/PYF8qewH3z

[Apertus @apertusllm]

@Ivrolan @Laz4rz @ETH_en @EPFL_en @cscsch @elvisnavah ?

[🤷 Nico Martin @nicodotdev]

Apertus Mini is now running entirely in your browser 🇨🇭
80+ tps for the 1.5B, 60+ tps for the 4B (on my M3). Fully client-side via Transformers.js + ONNX + WebGPU.

[Apertus @apertusllm]

Congratulations to each of the 102 authors of the #Apertus v1 report, officially published today ahead of the presentation at #ACL2026NLP in July. Follow @aclmeeting for updates https://t.co/Bl6jtQXErM