Common String Format Validation R package checkstring version 0.2.0 Validates common string formats including financial identifiers (ISIN, CUSIP, SEDOL, FIGI, IBAN, LEI), publication identifiers (ISBN, ISSN, DOI, ORCID), and general formats (email, UUID, URL, semver), with check digit verification where applicable. Software Depends: R (>= 4.1.0) Suggests: curl, testthat (>= 3.0.0) Maximilian Mücke <muecke.maximilian@gmail.com> Comprehensive R Archive Network (CRAN) Maximilian Mücke [aut, cre] (ORCID: <https://orcid.org/0009-0000-9432-9795>) MIT + file LICENSE (https://CRAN.R-project.org/package=checkstring/LICENSE) 2026-06-29 application/tgz https://CRAN.R-project.org/package=checkstring doi:10.32614/CRAN.package.checkstring