# Excelize — High-Performance Go Library for Excel Spreadsheets

> Excelize is a Go library for reading, writing, and manipulating Microsoft Excel files (XLSX/XLSM/XLTM). It supports formulas, charts, pivot tables, images, conditional formatting, and streaming writes for large datasets.

## Install

Save in your project root:

# Excelize — High-Performance Go Library for Excel Spreadsheets

## Quick Use
```bash
go get github.com/xuri/excelize/v2
```
```go
f := excelize.NewFile()
f.SetCellValue("Sheet1", "A1", "Hello")
f.SaveAs("output.xlsx")
```

## Introduction
Excelize provides a pure Go implementation for reading and writing Office Open XML spreadsheet files. It lets backend services generate complex Excel reports, import user-uploaded spreadsheets, and process large datasets without relying on external binaries or COM automation.

## What Excelize Does
- Reads and writes XLSX, XLSM, and XLTM files with full formula support
- Creates charts (bar, line, pie, scatter, and 50+ chart types)
- Generates pivot tables and applies conditional formatting rules
- Embeds images, shapes, and comments into cells
- Streams rows for writing spreadsheets with millions of rows in constant memory

## Architecture Overview
Excelize operates on the underlying ZIP-packaged XML structure of Office Open XML files. It parses shared strings, style sheets, and worksheet XML into in-memory Go structs, applies edits, then serializes back to valid OOXML. The streaming writer bypasses full in-memory representation by flushing rows directly to the output, enabling constant-memory writes for large files.

## Self-Hosting & Configuration
- Install via `go get github.com/xuri/excelize/v2`
- Zero external dependencies beyond the Go standard library
- Use `StreamWriter` for files exceeding available RAM
- Set default fonts, number formats, and date styles via `Style` structs
- Supports password-protected workbook decryption

## Key Features
- Pure Go with no CGO or system dependencies
- Streaming writer handles millions of rows in constant memory
- 170+ formula functions evaluated natively
- 50+ chart types with full customization
- Thread-safe concurrent read access to workbooks

## Comparison with Similar Tools
- **Apache POI (Java)** — mature but requires JVM; Excelize is a single Go binary
- **openpyxl (Python)** — Python-only; Excelize integrates into Go services natively
- **SheetJS (JS)** — browser-focused; Excelize targets server-side batch processing
- **xlsx2csv** — read-only conversion; Excelize supports full read-write-chart workflows
- **Google Sheets API** — cloud-dependent; Excelize works fully offline

## FAQ
**Q: Can Excelize handle very large files?**
A: Yes, the StreamWriter API writes rows incrementally, keeping memory constant regardless of row count.

**Q: Does it support formulas?**
A: Excelize supports setting formula strings and evaluating 170+ built-in functions.

**Q: Is Excelize thread-safe?**
A: Concurrent reads are safe. Writes to a single file should be serialized.

**Q: Can I read password-protected Excel files?**
A: Yes, Excelize supports decrypting workbooks protected with a password.

## Sources
- https://github.com/qax-os/excelize
- https://xuri.me/excelize/

---
Source: https://tokrepo.com/en/workflows/asset-3188eebe
Author: AI Open Source