Converting from Excel formats to csv is something I've had to do many times in my career - usually to get the data into a database-import friendly format. The problem with xlsb is that it's a binary/zip format where support isn't great.

JavaScript is my goto language, but there's no library that specifically deals with the binary xls format.

UK EVENTAttend ffconf.org 2024

The conference for people who are passionate about the web. 8 amazing speakers with real human interaction and content you can't just read in a blog post or watch on a tiktok!

One sheet with Libreoffice

I got this from method from a stackoverflow answer and it works well enough - but doesn't scale easily to multiple sheets, nor does it allow for any specific handling of fields (which hasn't been a problem for me as yet).

$ soffice --headless --convert-to csv file.xlsb

This uses the soffice binary that ships as part of Libreoffice. It's likely soffice isn't in your path, so you can find it here:

  • Mac: /Applications/LibreOffice.app/Contents/MacOS/soffice
  • Windows: "C:\Program Files\LibreOffice 5\program\soffice.exe"
  • Linux - I'm not so sure, but you might find libreoffice works

Multi-sheet and/or special field handling

For multiple sheets you can use macros in Libreoffice, but you'll need to edit the sheet ahead of time which wasn't practical in my case. So we turn to python for processing.

I'm not a regular python coder, so my instructions below will be hacky, but hopefully mean that it's easy for someone whose unfamiliar with python can get it going.

This python code was tested with python3 (see note at the end for python2 support).

We'll make two files:

  • requirements.txt
pyxlsb==1.0.6
  • extract.py
import sys
from pyxlsb import open_workbook

if len(sys.argv) < 2:
    raise ValueError('You need to pass in an xlsb filename')

def toString(s):
    if s is None: return ''
    # change `str` to `unicode` if python2
    if isinstance(s, (str)): return s
    # note that floats are default for numbers
    # you may want to use `repr(int(s))`
    return repr(s)

with open_workbook(sys.argv[1]) as wb:
    for sheetname in wb.sheets:
        # make a new file for each sheet
        f = open(sheetname + ".csv", "w+")
        with wb.get_sheet(sheetname) as sheet:
            for row in sheet.rows():
                values = [r.v for r in row]
                f.write(','.join(map(toString, values)) + "\n")

To use the code above, first install the dependencies then run the extract.py with a single argument of the xlsb file and the program will stream out the CSV output.

$ pip install -r requirements.txt
$ python extract.py file.xlsb

If this works, it will create individual files for each sheet. If you want to combine all the sheets into a single file (assuming they have the same structure), then you can use this command to add your own header and collect the data without their csv header, into a single file:

$ (echo "col1,col2,col3,etc" ; tail +2 -q *.csv) > final.csv

Working around python

When I run the python command I get the following error:

Traceback (most recent call last):
  File "extract.py", line 2, in <module>
    from pyxlsb import open_workbook
ModuleNotFoundError: No module named 'pyxlsb'

Somehow my python paths aren't configured correctly, but pip was able to install the dependency so it's somewhere on my machine. I solve this doing the following:

  1. Discover where the dependencies are installed: pip show pyxlsb | grep Location
  2. Use PYTHONPATH

So my command now reads:

PYTHONPATH=/usr/local/lib/python3.7/site-packages python extract.py file.xlsb

An alterative method to get the dependency to be found, a way that I suspect is hacky, is to change the line import sys for the following two lines:

import sys
sys.path.insert(0, '/usr/local/lib/python3.7/site-packages')  # location of src

Now the dependency can be used. Probably very bad method, but frankly all the examples around python expect the user to know how this stuff should be configured which can lead to some frustration…