What is Mammoth CSV?

Spreadsheet power without the bloat

Mammoth CSV is a Windows-based tool designed to handle ultra-large CSV files with ease—far beyond Excel’s typical one-million-row limit. It offers powerful, Excel-style data manipulation while staying lean on memory and fully offline, ensuring your data never leaves your machine.

Efficient ETL capabilities for structured data workflows

Mammoth CSV extends beyond traditional spreadsheet functionality, offering agile ETL capabilities for complex workflows. Users can define, save, and reuse data transformation sequences across similar datasets. The application supports immediate data preview, column selection and renaming, and type assignments to resolve ambiguities. Once configured, the full dataset is loaded into memory for detailed exploration using multi-level filtering.

Advanced data transformation and aggregation

Mammoth CSV includes a powerful formula language for applying complex transformations and enriching datasets. Users can construct multilevel pivot tables with flexible grouping options and a wide range of aggregation functions, enabling detailed analysis across large and structured data.

Step-by-step export to standard formats

Each stage of the workflow can be exported in either Excel or CSV format, allowing for easy sharing, archiving, or further processing in external tools.

Quick start. Analyzing taxi traffic in New York

This example is based on the public dataset that can be found here .

It is a thirty million lines dataset with detailed taxi trips data for one year.

Tutorial Overview

In this tutorial, we will build a workflow to clean and prepare raw data, followed by an analysis of traffic patterns. The focus will be on identifying trends by day of the week and categorizing trips based on their duration.

First step: preview and load data

When you select the file to load an instant preview of data will be available.