Preview first
Open the dataset and inspect columns, row samples, and structure before deciding how to clean or transform it.
10 million row CSV
Open a 10 million row CSV without uploading it
DataOlllo gives analysts a local desktop workflow for very large CSV files, from quick previews to filtering, cleanup, splitting, and summaries.
Filter at scale
Narrow millions of rows by column values, ranges, and text patterns so you can focus on the records that matter.
Export only what matters
Create smaller CSV outputs from selected rows or columns for reporting, review, sharing, or downstream processing.
Common questions
Can I open a 10 million row CSV on a laptop?
Yes, with the right local workflow. DataOlllo is designed for large datasets that are uncomfortable in general-purpose spreadsheet-style tools.
Do I need to write code?
No. DataOlllo provides visual tools for opening, filtering, merging, splitting, and summarizing large files.