TabPFN-3.5: Technical Report

Benjamin Jäger; Nick Erickson; Léo Grinsztajn; Felix Birkel; Klemens Flöge; Oscar Key; Kürşat Kaya; Jonas Kübler; Adèle Frankel; Tobias Schröder; Anurag Garg; Jan Hendrik Metzen; David Salinas; Simon Bing; Kristina Collins; Tuana Çelik; Vahid Balazadeh; Lydia Sidhoum; Tomás Pereda; Brendan Roof; Andrej Tschalzev; Siyuan Guo; Philipp Singer; Lennart Purucker; Jake Robertson; Marie Salmon; Philipp Jund; Jerry Chen; Diana Kriuchkova; Arthur Cahu; Eliott Kalfon; Adrian Hayler; Georg Grab; Vitor Monteiro; Lilly Wehrhahn; Dominik Safaric; Clara Cornu; Alan Arazi; Rylee Grace; Simone Alessi; Mihir Manium; Bernhard Schölkopf; Yann LeCun; Madelon Hulsebos; Sauraj Gambhir; Noah Hollmann; Frank Hutter

arXiv · 2609.17895

TabPFN-3.5: Technical Report

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Abstract

We introduce TabPFN-3.5, our new flagship Tabular Foundation Model. It significantly outperforms its predecessor, TabPFN-3, and all existing baselines across a broad range of tabular problems. TabPFN-3.5 sets a new state of the art on standard tabular prediction in TabArena, and extends it to the data practitioners encounter in practice: non-i.i.d. data with temporal or grouped splits, tables with strings, text and images, high-cardinality categorical features, and wide tables with many features. These gains carry over to our task-specific harnesses: state of the art on relational data and stronger time-series forecasting. For faster inference, our variant TabPFN-3.5-Fast runs up to 3x faster than TabPFN-3 while keeping most of the accuracy gains. In addition, we upgrade TabPFN-3.5-Plus, expanding our multimodal capabilities with advanced text and date handling alongside proprietary inference optimizations. Finally, we release a new version of our Thinking mode, TabPFN-3.5-Thinking, which scales inference-time computation to push the state of the art further. It benefits from our stronger base model and from inference-time improvements that make it up to 12x faster than TabPFN-3-Thinking.

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Benjamin Jäger, Nick Erickson, Léo Grinsztajn, Felix Birkel, Klemens Flöge, Oscar Key, Kürşat Kaya, Jonas Kübler, Adèle Frankel, Tobias Schröder, Anurag Garg, Jan Hendrik Metzen, David Salinas, Simon Bing, Kristina Collins, Tuana Çelik, Vahid Balazadeh, Lydia Sidhoum, Tomás Pereda, Brendan Roof, Andrej Tschalzev, Siyuan Guo, Philipp Singer, Lennart Purucker, Jake Robertson, Marie Salmon, Philipp Jund, Jerry Chen, Diana Kriuchkova, Arthur Cahu, Eliott Kalfon, Adrian Hayler, Georg Grab, Vitor Monteiro, Lilly Wehrhahn, Dominik Safaric, Clara Cornu, Alan Arazi, Rylee Grace, Simone Alessi, Mihir Manium, Bernhard Schölkopf, Yann LeCun, Madelon Hulsebos, Sauraj Gambhir, Noah Hollmann, Frank Hutter. 2026-09-15. TabPFN-3.5: Technical Report. https://arxiv.org/abs/2609.17895

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