Aggregate CSV Files Online
Group and aggregate CSV files by any column directly in your browser. Calculate sum, average, min, max, and count for any numeric column — no upload required.
About this tool
Group and summarise a CSV file by any column combination. Compute SUM, AVG, MIN, MAX, and COUNT for numeric columns. Download the aggregated result ready for reporting or further analysis — all in your browser.
Frequently Asked Questions
What aggregation functions does the CSV aggregate tool support?
SUM, AVG (mean), MIN, MAX, and COUNT. You can apply multiple functions to the same column and group by any number of columns.
Can I group by multiple columns when aggregating a CSV file?
Yes. Add multiple group-by columns and the aggregations are computed for each unique combination of values across those columns.
What happens to non-numeric columns when aggregating a CSV file?
SUM, AVG, MIN, and MAX apply to numeric columns only. COUNT works on any column type and counts non-null values. Non-aggregated, non-grouped columns must be excluded from the output.
Is my data private?
Yes — completely. Your file is never uploaded to any server. Everything runs locally in your browser using WebAssembly — processing happens entirely inside your tab. Once you close the tab, nothing is retained.
What is the maximum file size?
The free limit is 50 MB. For larger files, performance depends on your device's available memory — most modern machines handle 500 MB to 1 GB comfortably.
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