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.
Quick answer: Get a quick health check of any dataset.
Related: Data Profiler · CSV Data Quality Checker · CSV Data Profiler · Open a Large CSV File Online · CSV Guides and Free CSV Tools
How to use the Check a CSV for Duplicates and Blanks Get a quick health check of any dataset.
The Data Profiler gives you a quick health check of a file. It shows the type of each column, missing values, duplicates, outliers and basic statistics such as minimum, maximum, mean and the most common values, with flags for likely problems. Analysts use it before cleaning or loading data, to decide what needs fixing. The report can be downloaded with an optional password.
Load your data Read the overview Review each column Tips Missing means empty or blank. Distinct means different values. A big gap between mean and median usually means outliers. Tick “Only columns with warnings” to find problems fast. Example Input: customers.csv
Output: 3 duplicate rows, 12 empty cells in email
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Frequently asked questions How do I find duplicates in a CSV? Open the file in the profiler. It lists duplicate rows and the missing values in each column.
Can I remove them afterwards? Yes. Use Remove duplicate rows in Data Transformation or the CSV formatter.
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.
Related pages Data Profiler : Profile a dataset for free: column types, missing values, duplicates, distributions and outliers, with a shareable HTML report. Nothing is uploaded.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.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. 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