South Korea’s largest telecom operator SK Telecom has unveiled A.X K1, the country’s first hyperscale artificial intelligence model with more than 500 billion parameters, marking a major step in Korea’s ambition to emerge as one of the world’s top three AI powers alongside the United States and China.
A.X K1 is a 519-billion-parameter foundation model developed under the Korean government’s Sovereign AI Foundation Model initiative. SK Telecom said the model will form the backbone of a national, full-stack AI ecosystem spanning semiconductors, data centres, models and services.
According to the company, A.X K1 is designed to function as a “teacher model” that transfers knowledge to smaller and specialised AI models, particularly those below the 70-billion-parameter scale. This approach is expected to accelerate innovation across Korea’s AI ecosystem by enabling companies and institutions to build tailored applications on top of a powerful core model.
SK Telecom said models operating at the 500-billion-parameter scale demonstrate more stable performance in complex reasoning and multilingual understanding, based on global benchmarks. These capabilities support advanced use cases such as high-complexity coding, autonomous agents and sophisticated decision-making tasks.
The operator plans to deploy A.X K1 as a public-facing AI foundation through its consumer and enterprise services. The model will be made accessible via A., also known as A-DoT, SK Telecom’s AI assistant platform, which already has more than 10 million subscribers. The initiative aligns with the Korean government’s “AI for Everyone” vision, aimed at making AI services widely available through voice calls, messaging, web platforms and applications.
Members of the SK Telecom-led consortium are expected to roll out industry-specific services built on A.X K1. These include manufacturing-focused AI through A. Biz, autonomous and real-time character interactions in games developed by Krafton, and AI-driven humanoid robotics. Liner, another consortium member, is expected to enhance its multilingual expert knowledge search services, which currently serve more than 11 million users globally.
Beyond applications, A.X K1 is also positioned as a test platform for Korea’s semiconductor industry. SK Telecom said operating AI models at the 500-billion-parameter scale is critical for validating memory bandwidth and inter-GPU communication performance, key bottlenecks in next-generation AI chips.
The SKT consortium comprises eight organisations: SK Telecom, Krafton, 42dot, Rebellions, Liner, SelectStar, Seoul National University and KAIST. Together, they have developed a sovereign AI platform based on proprietary technologies across the entire value chain, including AI semiconductors, AI data centres, models and services.
More than 20 institutions, including SK hynix, SK Innovation and SK Broadband, have already submitted letters of intent to participate in real-world validation of A.X K1, SK Telecom said.
The consortium plans to release A.X K1 as an open-source model for companies across Korea’s AI ecosystem. Open APIs and access through major developer communities and SK Telecom platforms are intended to support AI agent development at scale. Portions of the training data will also be disclosed through public and private platforms as part of a broader effort to raise national AI competitiveness.
“This marks a new inflection point in Korea’s journey toward becoming one of the world’s top three AI nations amid intensifying global competition,” said Kim Tae-yoon, Head of Foundation Model Office at SK Telecom. “As Korea’s leading AI company, we will continue driving our efforts to deliver AI for Everyone.”
