ModernBERT-Ja

Japanese adaptation of the ModernBERT encoder (Warner et al., 2024) in three sizes: 30M, 130M, and 310M. Released February–May 2025 under the MIT license. The 30M variant is SB Intuitions' most-downloaded model by a wide margin (24K+ monthly downloads on HuggingFace), reflecting demand for efficient Japanese encoder models in retrieval, classification, and embedding use cases where a small encoder is preferred over a decoder LLM.