SheetJS
Parser and writer for various spreadsheet formats. Pure-JS cleanroom implementation from official specifications, related documents, and test files Emphasis on parsing and writing robustness, cross-format feature compatibility with a unified JS representation, and ES3/ES5 browser compatibility back to IE6.
This is the community version. We also offer a pro version with performance enhancements, additional features like styling, and dedicated support.
File format support for known spreadsheet data formats: