Ledger.py: command-line, double-entry accounting in python

Ledger.py is a simple, command-line, double-entry accounting system. It reads transactions written in a simple format from a text file and produces summary reports as text or an excel spreadsheet.

Because transaction data is stored as text, it can be managed using a version control system like git. This makes it easy to maintain an audit trail.

Ledger.py is like John Wiegley's Ledger, but simpler.

What it does

Ledger.py reads an input file that's written in a simple file like this:

2013-01-01 I began the year with $1000 in my cheque account.
  Assets:Bankwest:Cheque      $1,000
  Equity:OpeningBalances      $1,000

2013-01-05 I bought some groceries and paid using the cheque account.
  Expenses:Food:Groceries    $98.53
  Assets:Bankwest:Cheque    -$98.53

2013-01-10 I bought some petrol, and paid using a credit card.
  Expenses:Motor:Fuel    $58.01
  Liabilities:Bankwest:Visa   $58.01

2013-01-15 I paid my electricity bill.
  Expenses:Electricity    $280.42
  Assets:Bankwest:Cheque  -$280.42

# I checked my bank statement on the 1st of Feb, and this is what it said.
VERIFY-BALANCE 2013-02-01 Assets:Bankwest:Cheque 621.05

and produces reports like this:

$./ledger.py examples/sample.transactions --print-balances
   $621.05 Assets:Bankwest:Cheque
 $1,000.00 Equity:OpeningBalances
   $436.96 Expenses
   $280.42   Electricity
    $98.53   Food:Groceries
    $58.01   Motor:Fuel
    $58.01 Liabilities:Bankwest:Visa

or this:

$./ledger.py examples/sample.transactions --print-balances --first-date 2013-01-05 --last-date 2013-01-15
 2013-01-05 2013-01-15   Change Account
    $901.47    $621.05 -$280.42 Assets:Bankwest:Cheque
  $1,000.00  $1,000.00    $0.00 Equity:OpeningBalances
     $98.53    $436.96  $338.43 Expenses
          -    $280.42  $280.42   Electricity
     $98.53     $98.53    $0.00   Food:Groceries
          -     $58.01   $58.01   Motor:Fuel
          -     $58.01   $58.01 Liabilities:Bankwest:Visa

or this:

$./ledger.py examples/sample.transactions --print-register Expenses
2013-01-05	 $98.53	 $98.53	Expenses:Food:Groceries	I bought some groceries and paid using the cheque account.
2013-01-10	$156.54	 $58.01	Expenses:Motor:Fuel    	I bought some petrol, and paid using a credit card.
2013-01-15	$436.96	$280.42	Expenses:Electricity   	I paid my electricity bill.

Getting started

The program is currently contained in a single python file. You can grab it and try it out like this:

# Grab the code
git clone git://github.com/mafm/ledger.py
cd ledger.py

# Generate some example reports
./ledger.py examples/sample.transactions --print-balances
./ledger.py examples/sample.transactions --print-register Expenses
./ledger.py examples/sample.transactions --print-register Expenses:Electricity

There is documentation outlining how to use the ledger.py in the Introduction file in the doc folder.

Requirements

As far as I know, ledger.py needs only Python 2.7. I am currently using it with Python 2.7.2+.

It would be nice to package ledger.py as a pip package, but that hasn't been done yet.

Testing

If you have nosetests installed, you can also run some tests. They are not comprehensive. If you have coverage installed, you can also look at the test coverage like this: nosetests --with-coverage --cover-package=ledger.

Status

I am using this program on a daily basis to do real work. I believe that what has been implemented is more or less correct. However, this program hasn't been extensively tested, so use it at your own risk.

Lots of useful easy-to-implement features have not yet been implemented. I am currently (April 2013) attempting to implement one or two of the missing features per week.

Origins

Ledger.py is similar to, and partly inspired by, John Wiegley's Ledger: http://www.ledger-cli.org/.

Ledger.py is also similar to some older double-entry accounting software I wrote using wxPython in 2004. Although that program had a GUI, and I used it for nearly ten years, it was more complex than ledger.py, and I found it less convenient to use.