# ExcelDataReader/ExcelDataReader

Lightweight and fast library written in C# for reading Microsoft Excel files

Repository: https://github.com/ExcelDataReader/ExcelDataReader
Canonical: https://ross.abutalabs.com/products/exceldatareader
Language: C#
License: MIT
License Family: permissive
Topics: excel, xlsb, xlsx, parser, xls, csharp, dotnet
Last push: 2026-07-06T19:25:14+00:00

## Health v2 (maintenance only)
Score: 81/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 91, release rhythm 57, longevity 100
- inputs: {"age_days": 4422, "days_push": 58, "days_rel": 78, "gap_med": 267, "n_releases_24m": 2}
- flags: none
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 4409, forks 1011 (observed 2026-08-28T04:08:48.450322+00:00)

## What it is
A lightweight and fast C# library for reading Microsoft Excel files (.xlsx, .xlsb, .xls) and CSV files. It provides a low-level reader interface plus an optional DataSet extension for populating System.Data.DataSet objects.

## Use cases
- read xlsx files in C#
- parse legacy xls spreadsheets in .NET
- import Excel data into a DataSet
- read xlsb binary Excel workbooks
- parse CSV files with encoding fallback
- extract spreadsheet data in a .NET application

## When to choose
- you need read-only Excel support in .NET with no dependencies on Office or COM interop
- you must support old BIFF2-BIFF8 .xls files as well as modern xlsx/xlsb
- you want a lightweight, fast streaming reader rather than a full spreadsheet library

## When to avoid
- you need to create, edit, or write Excel files
- you need formatting, charts, or formula evaluation
- you are not on a .NET-compatible platform

## Facets
- artifact type: library
- maturity: stable
- function: parser, file-system
- domain: files, developer-tools, spreadsheets
- platform: dotnet, cross-platform
- tags: excel, xlsx, xlsb, xls, csv, csharp, data-import, spreadsheet-reader

## Member repositories
- ExcelDataReader/ExcelDataReader (main) score 81

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:08:48.450322+00:00.
- Health v2: computed from the inputs above; adoption is never an input.
- Inferred fields (summary, facets, guidance): AI-extracted, prompt v1, taxonomy v1, on 2026-08-29T18:21:04.267142+00:00, confidence not recorded.
  - readme: https://github.com/ExcelDataReader/ExcelDataReader (fetched 2026-08-28T04:08:48.450322+00:00, sha d53ff82dc2b2)
- Data as of 2026-08-30T08:39:29.467469+00:00.