nissl-lab/npoi

a .NET library that can read/write Office formats without Microsoft Office installed. No COM+, no interop. observed · 2026-08-28

github.com/nissl-lab/npoi · homepage · C# · Apache-2.0 (permissive) observed · 2026-08-28

Health v2 · maintenance only

83/100

Activity 99
Release rhythm 53
Longevity 100

How is this computed?

round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10) — computed 2026-09-03. Adoption (stars, forks) is never an input.

gap_med: 102
age_days: 4992
days_rel: 152
days_push: 9
n_releases_24m: 6

Full methodology

Adoption not part of the score

6191 stars · 1491 forks observed · 2026-08-28

What it is AI-extracted, prompt v1, taxonomy v1, 2026-08-29, confidence not recorded

NPOI is a .NET library, a port of Apache POI, that reads and writes Office file formats (xls, xlsx, docx) without requiring Microsoft Office or COM interop. It supports cell styles, data formats, and formulas, and works across Windows and Linux on .NET Framework, .NET Standard 2.0/2.1, and .NET 8.

Use cases

generate excel reports from .net without office installed
read xlsx files in a .NET Core app on Linux
export data to xls spreadsheets from ASP.NET
import excel data into a database with C#
create Word docx documents programmatically in .NET
manipulate excel formulas and cell styles without COM interop

When to choose

you need to read/write Excel or Word files in .NET without installing Microsoft Office
you need cross-platform (Linux/Windows) Office file processing
you need support for legacy xls (BIFF) and modern xlsx formats
you want a free option as a startup, freelancer, or hobbyist

When to avoid

your organization generates revenue and you cannot accept the Open Source Maintenance Fee EULA on binaries since 2.8.0
you need Office formats beyond xls/xlsx/docx (e.g., pptx)
you prefer a fully permissive license with no revenue-based fees

Facets

library · maturity active

serialization file-system developer-tools files spreadsheets developer-tools cross-platform dotnet cross-platform windows excel openxml biff word office-formats no-interop apache-poi-port spreadsheet linux macos

2 sources

readme: https://github.com/nissl-lab/npoi · fetched 2026-08-28 · 6cd1e3c20b63
homepage: http://nissl-lab.github.io/npoi/ · fetched 2026-08-29 · 6ade58115881

Member repositories

Repository	Role	Health v2
nissl-lab/npoi	main	83

For agents

markdown · JSON · MCP: product_card(name="nissl-lab/npoi")

Data as of 2026-08-30T08:39:29.467469+00:00 · Report a problem