Merge Multiple Datasets Instantly.
Combine dozens of files, append rows, and align mismatched columns in seconds after you open the large CSV files locally.
Download Data MergerDownloads standard DataOlllo PC AppStop Copy-Pasting Across 50 Files
BEFORE
Manual File Appending.
Jan_Data.csv (Opened)
Feb_Data.csv (Opened)
Ctrl+C (Copying 150,000 rows)...
Switching to Master.xlsx
Traditional Spreadsheets: Clipboard is full...
↓
AFTER
Seamless Multi-File Batch Append.
Source_File
Date
Location
Sales
Jan_Data.csv
2023-01-15
East
$1,200
Feb_Data.csv
2023-02-08
West
$950
Mar_Data.csv
2023-03-22
North
$2,100
50 files appended in 1.2s
DataOlllo intelligently combines multiple datasets into one master view without opening a single spreadsheet.
Master Your Datasets
Folder Batch Merge
Just point to a folder containing hundreds of CSVs. DataOlllo reads and appends them into one dataset that you can inspect with the large CSV viewer.
Auto Column Alignment
Different standard headers across files? DataOlllo auto-aligns columns intelligently even if they are in different orders.
Flexible Joins
Need to join instead of append? Perform Left, Right, Inner, or Outer joins via matching keys with no SQL required.
Your data is yours. Keep it that way.
DataOlllo processes everything locally on your machine.
No cloud uploads. No leaks. No "Third Party" risk.