An Expanded Massive Multilingual Dataset for High-Performance Language Technologies (HPLT)

Abstract: Training state-of-the-art LLMs requires vast amounts of clean and diverse textual data. However, building suitable multilingual datasets remains a challenge. In this work, we present HPLT v2, a collection of high-quality multilingual monolingual and parallel corpora, extending prior work of the HPLT project. The monolingual portion of the data contains 8T tokens covering 193 languages, while the parallel data contains 380M sentence pairs covering 51 languages. We document the entire data pipeline and release the code to reproduce it. We provide extensive analysis of the quality and characteristics of our data. Finally, we evaluate the performance of LLMs and machine translation systems trained on HPLT v2, demonstrating its value.