A Python library for writing .xlsx files.

pip install xlsxcessive==1.1.3


tests Ruff Code style: Black https://img.shields.io/badge/skeleton-2023-informational

XlsXcessive provides a Python API for writing Excel/OOXML compatible .xlsx spreadsheets. It generates the XML and uses openpack to wrap it up into an OOXML compatible ZIP file.

Creating a Workbook

The starting point for generating an .xlsx file is a workbook:

from xlsxcessive.workbook import Workbook

workbook = Workbook()

Adding Worksheets

The workbook alone isn't very useful. Multiple worksheets can be added to the workbook and contain the cells with data, formulas, etc. Worksheets are created from the workbook and require a name:

sheet1 = workbook.new_sheet('Sheet 1')

Working With Cells

Add some cells to the worksheet:

sheet1.cell('A1', value='Hello, world')
sheet1.cell('B1', value=7)
sheet1.cell('C1', value=3.14)
sheet1.cell('D1', value=decimal.Decimal("19.99"))

Strings, integers, floats and decimals are supported.

Add cells via row index and column index:

sheet1.cell(coords=(0, 4), value="Added via row/col index")

This form of addressing is useful when iterating over data structures to populate a sheet with cells.

Calculations With Formulas

Cells can also contain formulas. Formulas are created with a string representing the formula code. You can optionally supply a precalcuated value and a shared boolean flag to share the formula across a number of cells. The first cell to reference a shared formula as its value is the master cell for the formula. Other cells may also reference the formula:

formula = sheet1.formula('B1 + C1', shared=True)
sheet1.cell('C2', formula) # master
sheet1.cell('D2', formula) # shared, references the master formula

Cells With Style

The library contains basic support for styling cells. The first thing to do is create a style format. Style formats are shared on a stylesheet on the workbook:

bigfont = workbook.stylesheet.new_format()
bigfont.font(size=24, bold=True)

Apply the format to cells:

sheet1.cell('A2', 'HI', format=bigfont)

Other supported style transformations include cell alignment and borders:

col_header = workbook.stylesheet.new_format()

Adjusting Column Width

It is possible to adjust column widths on a sheet. The column width is specified by either number or index:

# these are the same column
sheet1.col(index=0, width=10)
sheet1.col(number=1, width=10)

TODO: Referencing columns by letters.

Merging Cells

Cells can be merged together. The left-most cell in the merge range should contain the data:

from xlsxcessive.worksheet import Cell
a3 = sheet1.cell('A3', 'This is a lot of text to fit in a tiny cell')

Save Your Work

You can save the generated OOXML data to a local file or to an output file stream:

# local file
save(workbook, 'financials.xlsx')

# stream
save(workbook, 'financials.xlsx', stream=sys.stdout)


This is certainly a work in progress. The focus is going to be on improving the features that can be written out in the .xlsx file. That means more data types, styles, metadata, etc. I also want to improve the validation of data before it is written in an incorrect manner and Excel complains about it. I don't think this library will ever be crafted to read .xlsx files. That's a job for another library that can hate its life.