CSV Cleaner

Instructions

1. Upload or drop one .csv or .xlsx file.
2. Review the issue cards. Safe fixes are already selected. Changes that can drop a meaningful row stay off.
3. Preview the recommended cleanup, or open Advanced options for dates, phones, missing values, and column rules.
4. Apply changes when the preview looks right. Undo, reset, or download the table on screen.

Example

One file can need more than one pass. This sample has a padded name, a repeated row, and a blank row.

name,city
  Ada ,Tokyo
Ada,Tokyo
, 

Trim whitespace, remove empty rows, and remove duplicate rows. The padded name becomes Ada, the blank row is dropped, and the repeated Ada,Tokyo row is removed. One data row remains.

Operations run in a fixed order

When more than one operation is selected, they run in this order: trim whitespace, collapse repeated spaces, normalize headers, normalize dates, remove phone separators, remove empty rows, remove rows with missing values, check email syntax, remove exact duplicate rows, then remove duplicates by column. A later step sees the table produced by the earlier steps.

Trimming can turn a padded row into an exact copy of another row. The duplicate step then removes that later copy. Header normalization never changes the cells themselves.

What the statistics mean

Each column reports how many cells are empty, how many distinct non-empty values it has, and how many extra copies those values have. An inferred type, such as integer or date, is only a description.

Leading zeros, phone numbers, and identifiers stay text. The cleaner does not convert a column because the statistics called it a number.

Limitations

• Safe fixes are selected when they are found. Dates, missing values, email deletion, and column rules stay off until you choose them.
• Normalize headers trims header names, replaces regular spaces with underscores, and adds _2 or _3 when names collide. It does not change cell values.
• Duplicates by column do nothing until you select at least one column.
• Exact duplicate matching does not ignore spaces or letter case.
• CSV and .xlsx up to 32 MB. The download is CSV. Save .xls as .xlsx first.