CSV Cleaner & Data Wrangler: Dedupe, Filter, Convert CSV Online

Drop a CSV or TSV file here

or click to browse — parsed entirely on your device

or paste

Cleaning pipeline (applied in order — click ✕ to remove a step)

Add an operation

Remove duplicates

Remove rows that repeat on selected columns.

Filter rows

Keep rows matching a condition.

Sort rows

Numeric-aware sorting.

Trim whitespace

Strip leading/trailing spaces.

Change case

Normalize capitalization.

Find & replace

Literal or regex, with case option.

Regex Case-sensitive

Split column

Split one column into several.

Merge columns

Combine two columns into one.

Remove column

Drop a column you don't need.

Rename column

Give a column a clearer name.

Drop empty rows

Remove rows where all cells are blank.

Column stats

Preview

Showing up to 100 rows

Export cleaned data

How it works

A clean-data pipeline in three steps — private by design.

1

Load your CSV

Drop a file or paste data. Large files are parsed in streaming chunks so the page stays fast.

2

Build a cleaning pipeline

Add operations — dedupe, filter, sort, trim, case, find & replace, split, merge — applied in order. Remove any step anytime.

3

Export anywhere

Download as CSV, TSV, JSON, Markdown, or SQL with inferred column types — ready for analysis, imports, or your database.

Why Prescosoft CSV Cleaner

Your file is read locally — never transmitted, never stored.
Safe for customer lists, payroll, and other sensitive data.
Unlimited rows and files, no account, no watermark.
Works offline after the page loads.

Typical online CSV tools

Upload your file to their server to process it.
Row limits, daily caps, and watermarks on exports.
Accounts and email signups before you can download.
Your data lives on their infrastructure afterwards.

Who is this for?

📊

Analysts & marketers

Clean exported campaign or CRM data — dedupe leads, normalize casing, drop junk rows — before loading into your BI tool.

🧑‍💻

Developers & data folks

Convert CSVs to SQL INSERT scripts with inferred types, or to clean JSON, without pasting data into a third-party service.

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Privacy-conscious users

Clean payroll, customer, or medical spreadsheets in complete privacy — the data never leaves your machine.

Frequently Asked Questions

What is a CSV cleaner?

A CSV cleaner is a tool that fixes messy spreadsheet data exported as CSV: removing duplicate rows, trimming stray whitespace, fixing inconsistent capitalization, filtering out rows you don't need, splitting combined columns, and converting the result into a clean format for analysis or import.

Is my CSV data uploaded to a server?

No. The CSV Cleaner runs entirely in your browser using Papa Parse and plain JavaScript. Your file is read locally and every operation — dedupe, filter, sort, export — happens on your device. Nothing is uploaded, stored, or sent anywhere, so it is safe to use with customer lists, financial data, and other sensitive spreadsheets.

Can it handle large CSV files?

Yes. Large files are parsed in streaming chunks so the page stays responsive, and the practical limit is your device's memory rather than a file-size cap. Files with hundreds of thousands of rows work well on a typical laptop or desktop browser.

What cleaning operations are supported?

Remove duplicates (all columns or specific ones), filter rows by conditions, sort by any column with numeric detection, trim whitespace, change text case, find & replace (with regex and case options), split one column into several, merge columns, remove or rename columns, drop empty rows and columns, and inspect per-column statistics with automatic type inference.

Can I convert CSV to JSON, SQL, or Markdown?

Yes. After cleaning, export the result as CSV, TSV, JSON (array of objects), Markdown table, or SQL — with CREATE TABLE and INSERT statements generated automatically using inferred column types (TEXT, INTEGER, REAL, or DATE).

Is the CSV Cleaner really free with no account?

Yes — completely free, no account, no signup, no watermarks, no file size caps, and no usage limits. It is part of the Prescosoft suite of privacy-first browser tools, so your data stays on your device.

Related guides

Text Toolkit

How to Clean Up Messy Text Data

Whitespace, casing, duplicates, and encoding — the classic text-level problems that make spreadsheet data hard to work with.

Read guide HTML Table Generator

Turn Spreadsheet Data into Clean HTML Tables

From raw CSV to a styled, responsive HTML table — paste, style, and export with inline or class-based CSS.

Read guide

More Prescosoft tools

📝

Your data. Your machine. Your call.

Clean and convert CSVs in seconds — privately, for free, forever.

Clean a CSV Now

CSV Cleaner &
Data Wrangler