plan says keeps newest
run result
undo-restore fix
empty file red error
review flags

Inspiration

I created CleanSheet to solve a common, frustrating problem: messy CSV files. Extra spaces, duplicate rows, inconsistent formatting, missing values, and invalid data can make a spreadsheet difficult to use. I wanted to build a simple tool that helps people clean their data without needing technical expertise or uploading private files to a server.

What it does

CleanSheet is a browser-based CSV cleaning tool. Users can import a CSV file and review suggested fixes, including duplicate detection, whitespace cleanup, and normalization of names, emails, phone numbers, dates, and currency values.

It also flags potentially problematic data, such as missing or invalid values and unusual numbers. Users remain in control: they can review explanations, apply or dismiss suggestions, undo changes, restore values, and export the cleaned CSV along with a change report.

How I built it

I built CleanSheet with AI coding assistance from Claude, using HTML, CSS, and JavaScript. The project includes a separate cleaning engine, a browser interface, sample CSV data, and a Node.js test file.

A key design decision was to keep the cleaning process transparent and user-controlled. CleanSheet uses keyword-based rules and instructions rather than an AI model to decide how to clean data. Files are processed in the browser, so the app does not need to upload CSV contents to a server.

Challenges and learning

One of my main challenges was turning a broad idea into a manageable project with clear features and a usable interface. I learned the importance of separating the cleaning logic from the interface, explaining why a change is suggested, and allowing users to reverse decisions instead of silently modifying their data.

Working with an AI coding assistant also taught me that generating code is only part of building a project. The implementation still needs to be reviewed and tested, and the features need to work together as a coherent product.

What's next

I want to continue improving CleanSheet's reliability, usability, and support for real-world CSV files. My goal is to make data cleaning more understandable, accessible, and privacy-conscious for everyone.

CleanSheet is my attempt to make spreadsheet cleanup less frustrating while keeping people in control of their own data.