How to Profile a Large Dataset Online

Before you model, join or load a dataset, find out what is in it. Profiling does that in a couple of minutes.

Open the Data Profiler

Profiling means summarising each column: its type, how many values are blank, how many are unique, the range of the numbers and the most common values. It also counts duplicate rows. It is the fastest way to find a bad column before it causes a bad result.

The Data Profiler does this in the browser and produces a report you can share as an HTML file, with an optional password. For very large files, use the large file mode with the profile option, which reads the file from disk in pieces instead of loading it whole.

Read the report with questions. Is any column mostly blank? Are numbers stored as text? Are there duplicate keys? Are the minimum and maximum plausible? Does a date column hold more than one format? Each answer points to a cleaning step in Data Transformation.

A profile shows what is there, not whether it is right. Compare counts with the source system and keep the report with the dataset as a record.

Open the Data Profiler

Related tool pages

  • CSV Data Quality Checker: Check a CSV for missing values, duplicates, outliers and wrong types in seconds, and share a report. Free, in your browser.
  • Check a CSV for Duplicates and Blanks: Find duplicate rows, empty cells and odd values in a CSV before you use it. See a report per column. Free, in your browser.
  • CSV Data Profiler: Profile a CSV in seconds: column types, missing values, duplicates, outliers and distributions, with a shareable report. Free, in your browser.
  • Open a Large CSV File Online: Open and explore a CSV too big for Excel: see rows and columns, filter with SQL and export. Works for 500 MB and more, in your browser.
  • CSV Viewer Online: Open a CSV file online and see its rows, column types, blanks and duplicates at a glance. Free, private, no upload.
  • Data Profiler Online: Profile a CSV, Excel, JSON or Parquet file online: rows, types, missing values, duplicates and statistics per column. Free, private, large files too.

How to use the Data Profiler: step by step

  1. Open the Data Profiler and load the file, or use large file mode.
  2. Read the column summaries and the duplicate count.
  3. Note the problems to fix.
  4. Download or share the report.

When to use the Data Profiler

  • Check a dataset before analysis
  • Find blank and duplicate-heavy columns
  • Share a quality report with a team
  • Profile a file too big for Excel

Example

Input: id,name,age 1,Ada,36 2,Alan,41

Output: age: integer, 0% missing, mean 38.5, min 36, max 41

Frequently asked questions

What counts as a duplicate row?

A row identical to an earlier one in every column.

What does the Data Profiler show?

Column types, missing values, duplicates, outliers and basic statistics, so you can judge the quality of a file at a glance. You can download the report, with an optional password.

Tip: Add a password when you share a profile report, since it can contain sample values.