Paid script
Books Audit Python script
One file you run on your own computer. Feed it a ledger CSV (and a bank CSV if you have one) and get a plain-English report of what deserves a second look.
Paid script
Books Audit Python script
Buy this script on its own for $19, one time. No membership needed. It runs on your own computer and nothing you enter leaves it. Read how it works and the questions below first.
The Financial Suite includes this and 9 more tools for $49. Members get this included. See the membership or sign in. Already bought it? Email me my access link.
How it works
How it works
The script is pure Python with no installs. It runs eight checks: possible duplicates, a Benford first-digit test with a chi-square p-value, robust outliers by vendor using the median and MAD, amounts just under an approval limit, weekend and month-end timing, vendor names that look like the same vendor, bank-to-ledger reconciliation including split deposits, and a Monte Carlo cash runway that resamples your own past months. It reads CSV exports from any accounting system, and a built-in --demo shows the report on sample data first. Flags are reasons to look, never proof of a problem.
FAQ
About this calculator
What do I need to run it?
Python 3.9 or newer. There is nothing else to install, and the data never leaves your computer.
What file format does it read?
CSV exports with a header row: a date, a description or payee, and either one amount column or debit and credit columns. Common column names are recognized automatically.
Is a flag proof of fraud or an error?
No. These are statistical screens. A flag means look at the transaction, and most have ordinary explanations.
Is this audit or accounting advice?
No. It is a general-information tool. It does not replace a bookkeeper, accountant or auditor.
Is anything saved?
No. The math runs in your browser and nothing you enter is sent to us.
Is this tax or financial advice?
No. It is a calculator for general information. Check the numbers against your own records, and ask an accountant before you act on them.
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Free
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General information, not tax or legal advice. How we write and check our tools.
Python scripts
Bookkeeper's Python Starter Scripts
Three small, readable Python scripts that do chores bookkeepers repeat by hand, with sample files so you can see each one work before using your own data.