PunkFix

Column Type Inference

Guess and cast column types (Number, Boolean, Date). 100% private—your data stays in your browser.

No uploadsNo signupInstant results
1

Upload CSV

Drop your dataset.

2

Analyze Types

We scan columns to guess data types.

3

View Schema

See the detected types for each column.

Click to upload or drag & drop

Supported files: CSV, TXT, JSON (Max 20MB)

Drop your file here

or click to browse

Any CSV file.

Max 20MB 100% Private

What This Tool Does

This tool scans your data to determine the underlying type of each column. It verifies if a column is 'safe' to treat as a number or date.

How It Works

1Upload the CSV.
2The tool scans all rows.
3It reports the inferred type for each header.
4Download the typed report or schema.

Input Format

Unknown CSV dataset.

Output Format

A Type Report or JSON Schema.

When to Use This Tool

  • Generating a `CREATE TABLE` SQL statement.
  • Documenting a dataset.
  • Checking for data type pollution.

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