The codebase for the paper entitled "cfr (v2024.1.26): a Python package for climate field reconstruction" in GMD. cfr aims to provide a universal framework for climate field reconstruction (CFR). It provides a toolkit for the processing and visualization of the proxy records, climate model simulations, and instrumental observations, the calibration and running of the proxy system models (PSMs, Evans et al., 2013), the preparation and running of the multiple reconstruction frameworks/algorithms, such as LMR (Hakim et al., 2016; Tardif et al., 2019) and GraphEM (Guillot et al., 2015), and the validation of the reconstructions, etc.