Spreadsheet and CSV Tools

CSV Cleaner

Process spreadsheet data with this csv cleaner entirely in your browser.

Your files stay in this browser. Each input file can be up to 4 MB and is held only in local memory.

How to use this calculator

  1. Load a local file or paste CSV text, adjust the available options, and review the result before downloading it.
  2. Review the live result and use Copy result when you need to share it.

How the calculation works

The browser parses the file in local memory. CSV fields preserve quoted commas, escaped quotation marks, and line breaks; files are not uploaded.

Processing rules

The browser parses the file in local memory. CSV fields preserve quoted commas, escaped quotation marks, and line breaks; files are not uploaded.

Step-by-step calculation

  1. Load a local file or paste CSV text, adjust the available options, and review the result before downloading it.
  2. The browser parses the file in local memory. CSV fields preserve quoted commas, escaped quotation marks, and line breaks; files are not uploaded.
  3. Check the displayed result, then copy it if needed.

Worked example

A CSV export can be trimmed while blank and duplicate records are removed.

Methodology and review

Who this is for

Analysts cleaning tabular exports before import.

Inputs and units

  • Local CSV file
  • Trim, empty-row, and duplicate options

Method

The browser parses quoted CSV fields, optionally trims cell boundaries, removes records that are empty under the selected rule, and deduplicates complete normalised rows.

Worked example

Rows differing only by outer spaces become equal after trimming and one duplicate can be removed.

Assumptions

  • Rows use a consistent delimiter and quoting convention.
  • Duplicate detection compares complete processed rows rather than choosing a business key.

Common mistakes

  • Removing duplicates without choosing the intended comparison
  • Overwriting the source before previewing

Limitations

  • Semantic duplicates with different spelling, punctuation, or number formatting are not inferred.
  • Review the preview before replacing an original data export.

How this tool was checked

Browser tests use quoted commas, escaped quotation marks, blank records, and duplicate rows without uploading the file.

Reference sources

Related tools

Calculation review: 21 August 2026. Published by Goldwave Dynamics Limited. This is an internal product review, not an independent certification.

Risk guidance

Frequently asked questions

Does this tool send my inputs anywhere?

No. The interactive calculation runs in your browser and this site does not submit tool inputs to a backend.

How should I use the result?

Check that the entered units and values match your situation, especially around dates, breaks, and rounding.

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