Skills

Clean Spreadsheet Data

Trims, standardizes and deduplicates messy spreadsheet data before analysis.

Install

npx skills add AI4Finance-Foundation/FinRobot --skill clean-data-xls -g -a claude-code -y
Category
Data and ML
Updated
11d ago
License
Apache-2.0
Context cost
Lightabout 600 tokens
Runs scripts
No, instructions only

What it does

Clean up messy spreadsheet data, trim whitespace, fix inconsistent casing, convert numbers-stored-as-text, standardize dates, remove duplicates, and flag mixed-type columns. Use when data is messy, inconsistent, or needs prep before analysis. Triggers on "clean this data", "clean up this sheet",...

Clean Data

Clean messy data in the active sheet or a specified range.

Environment

  • If running inside Excel (Office Add-in / Office JS): Use Office JS directly (Excel.run(async (context) => {...})). Read via range.values, write helper-column formulas via range.formulas = [["=TRIM(A2)"]]. The in-place vs helper-column decision still applies.
  • If operating on a standalone .xlsx file: Use Python/openpyxl.

Workflow

Step 1: Scope

  • If a range is given (e.g. A1:F200), use it
  • Otherwise use the full used range of the active sheet
  • Profile each column: detect its dominant type (text / number / date) and identify outliers

Step 2: Detect issues

IssueWhat to look for
Whitespaceleading/trailing spaces, double spaces
Casinginconsistent casing in categorical columns (usa / USA / Usa)
Number-as-textnumeric values stored as text; stray $, ,, % in number cells
Datesmixed formats in the same column (3/8/26, 2026-03-08, March 8 2026)
Duplicatesexact-duplicate rows and near-duplicates (case/whitespace differences)
Blanksempty cells in otherwise-populated columns
Mixed typesa column that's 98% numbers but has 3 text entries
Encodingmojibake (é, ’), non-printing characters
Errors#REF!, #N/A, #VALUE!, #DIV/0!

Step 3: Propose fixes

Show a summary table before changing anything:

ColumnIssueCountProposed Fix

Step 4: Apply

Read the whole SKILL.md on GitHub

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