HelloCSV

HelloCSV is a frontend JavaScript library that lets developers embed a fully-featured CSV and spreadsheet importer directly into their web applications. It handles file uploads, column validation, data transformation, and user progress saving entirely in the browser. You define the required and optional columns for your data, and HelloCSV provides a clean interface for users to drag-and-drop files or manually enter information.

The tool works with any JavaScript application, including those not built with React, and can be added with just a few lines of code. It validates data against rules you set, like requiring certain fields or checking for unique email formats. A key feature is local storage persistence, which means users won't lose their progress if they accidentally refresh the page. It also supports multiple sheets from a single upload, handling complex data relationships, and can be extended to parse XLSX files and other formats.

HelloCSV is ideal for developers building internal admin tools, SaaS products, or any application that requires users to upload structured data. It eliminates the need to build custom CSV parsing logic from scratch. Use cases include uploading employee lists, customer data, inventory sheets, or any scenario where clean, validated data import is needed without sending sensitive information to external servers.