METLIN SMRT dataset contains retention times for 80038 molecules, their PubChem numbers, structures and molecular descriptors and fingerprints calculated with program . All the retention times in the dataset were obtained on a liquid chromatograph coupled with quadrupole time-of-flight mass spectrometer (HPLC-Q-TOF) with Zorbax Extend C-18 reverse-phase column (2.1 x 50mm, 1.8 µm) using identical chromatographic method for all compounds.