Optimal Plot Size Estimation for Field Experiments R package optsize version 0.1.0 Provides methods for determining optimum plot size and shape in field experiments using Fairfield-Smith's variance law approach. It will evaluate field variability, determine optimum plot size and shape and study fertility trends across the field. Software Imports: ggplot2 Suggests: knitr, rmarkdown Y.A. Garde <y.garde@yahoo.co.in> Comprehensive R Archive Network (CRAN) Y.A. Garde [aut, cre, cph] (ORCID: <https://orcid.org/0000-0002-0297-316X>), S.G. Patil [aut], M.S. Shitap [aut] GPL (>= 3) 2025-10-06 application/tgz https://CRAN.R-project.org/package=optsize doi:10.32614/CRAN.package.optsize