NIAS-db 1.0 is an open-source software in R, developed with the Shiny framework and the Chromium Portable v16.0.3153.0 web browser (32-bit) for exploring databases of theoretical oligoesters and phenolic oligomers. NIAS-db 1.0 is freely available under the GPLv3 license. It is packed as an executable file of 1.0 GB. It runs out of the box without need for computer skills or administrative rights, when installed in a folder in which the user has full read/write access (not necessarily C/Program files). Once installed, the uncompressed database reaches 10.0 GB. The NIAS-db Windows command file available at the folder root launches the interface. Queries can be performed from either the neutral chemical formula or the monoisotopic mass with a mass tolerance (mDa).