hucre

Zero-dependency spreadsheet engine — XLSX, CSV, ODS

Drop an XLSX file to parse it. All cell types, shared strings, dates, and merged cells are handled correctly.

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Drop .xlsx file here or click to browse

Options

Sheets

Header Row

Read Styles

Detect Dates

Drop an XLSX file to see parsed data

Generate XLSX files from JSON data. Define columns, styles, and sheet options.

JSON Data

Sheet Options

Sheet Name

Freeze Rows

Auto Filter

Auto Width

Columns

Column Config (JSON)

Click "Generate XLSX" to preview

Parse and generate CSV with auto-delimiter detection, type inference, and RFC 4180 compliance.

CSV Input

Parse Options

Delimiter

Has Header

Type Inference

Skip Empty

Edit CSV and click Parse

Validate spreadsheet data against a schema. Type coercion, pattern matching, min/max, enums.

Sample Data (CSV)

Schema Definition (JSON)

Click "Validate" to check data against schema

Stream large XLSX files row-by-row without loading everything into memory. Or generate XLSX incrementally with XlsxStreamWriter.

Number of rows to generate

Number of columns

Click "Generate & Stream" to write and read back rows

Read and write OpenDocument Spreadsheet (.ods) files — compatible with LibreOffice, Google Sheets, and other open-source tools.

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Drop .ods file here or click to browse

Or generate ODS from JSON

Drop an ODS file or click "Generate ODS"

Convert XLSX, CSV, or ODS files to HTML table or Markdown format.

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Drop .xlsx, .csv, or .ods file

Or paste CSV

Options

First Row as Header

Include Styles (HTML)

Drop a file or paste CSV, then click "HTML" or "Markdown"

Apply Excel number formats to values. formatValue(value, numFmt) renders any cell value with its format string.

Value

Format String

Quick Examples

Click "Format" or pick a quick example