Group CSV Rows into Useful Summaries.

DataOlllo lets you group tabular records and calculate summaries locally. Choose a category and numeric measure, then validate the grouped result. For a large source, follow the 10 million row CSV workflow.

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Traditional Spreadsheets Pivot Tables Crash on Millions of Rows

BEFORE
Spinning Wheels and Crashes.
Date
Category
Sales
Calculating PivotTable...
Row 1,048,576 / 5,000,000
Application Not Responding
↓
AFTER
Illustrative grouped summary.
Category (Group)
Sum(Sales)
Electronics
$14,500,200
Apparel
$8,230,000
Home & Garden
$5,100,500
5M rows grouped in 1.2s

DataOlllo combines a large CSV viewer with a fast local engine for summarizing massive datasets.

Data Wrangling, Simplified

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Multiple Aggregations

Sum, Count, Average, Min, and Max. Apply multiple operations to different columns simultaneously.

Multi-Level Grouping

Group by Year, then Region, then Product exactly like a pivot table, but without the lag.

0

Zero Code Required

Choose grouping columns and a summary operation. Check that amounts are numeric, distinguish row counts from unique customers, and compare the total against your source before export.

Your data is yours. Keep it that way.

Standard grouping operations run locally on your machine.
Optional online AI features have separate data flows; review the privacy policy for sensitive data.

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