Open source tools for Australian accountants

Check workpaper packs, explore cash shortfalls and inspect the calculations.

Built by Ryan Duguid, a Senior Accountant in Newcastle, NSW. This personal site does not accept professional engagements.

Last reviewed 6 October 2026.

Compare profit with cash flow

Lumbridge Services is a fictional Newcastle maintenance business. Delay one customer receipt by 45 days and inspect the cash gap in its Excel forecast. The quarter’s profit stays the same.

Excel chart of weekly closing cash after a 45-day receipt delay, showing the cash gap against the assumed buffer — 13-week forecast with one receipt paid 45 days late. Weekly closing cash falls to −$25,160 against a $15,000 buffer, then recovers to $67,320 by December, the same as without the delay. Exported from the supplied workbook in Excel 16.0 on 13 October 2026. Capture record.

Choose a task

Use accounting functions in Excel

Ozzit provides worked GST, financial year, depreciation and loan formulas. Try them in Microsoft 365 or Excel 2024 or later.

Browse ten worked formulas

Review a month-end close

Accounting Review Pipeline includes a fictional July close with eight exceptions and a $250 creditors difference. Read the report here or rerun it with Git and Python.

Reproduce the sample report

Calculate a Coal LSL levy

Calculate eligible wages and see which formula applies. It runs in your browser with nothing to install.

Open the Coal LSL calculator

Check a BAS pack before manager review

Accounting Review Pipeline checks a fabricated BAS pack for missing work and unresolved items. Read the findings here or rerun the checks with Python.

Open the Workpaper Review Gate

Browse tools by accounting task

See how the Coal LSL levy is calculated

Coal LSL / fictional result

The browser calculator applies section 3B, names the formula and rounds only at the final step.

One employee, one month. Enter each amount, including zero, to see which formula applies. The full calculator treats a blank amount as $0.00.

Base rate of pay

Overtime and penalty

Allowances

Formula A, base rate plus bonuses: $6,000.00
Formula B, 75% of the aggregate: $7,125.00
Eligible wages, the greater of the two: $7,125.00
Levy at 2.7%, before rounding: $192.3750
Formula B applies. Levy payable, rounded once at the end: $192.38

Fictional figures, calculated in your browser. This site’s code sends and stores none of them; the Privacy page covers what Cloudflare adds when it delivers pages. This is the section 3B(1) base rate branch without bonuses, so use the full calculator for annual salary, casual and bonus frequency.

Open the Coal LSL calculator Open the evidence register

View the fixed calculator example

Coal LSL calculator result showing Formula B, eligible wages, levy and the applied section 3B branch for a synthetic example — Default synthetic example: $6,000 base pay, $3,000 overtime and penalty, $500 allowances. This screenshot stays fixed when you edit the figures above.

Try each tool with fictional data first

Use the sample files to check what each tool accepts, refuses and explains before using it in a firm.

Browse reproducible evaluations Set up AI tools

Before you use a tool, check its version and limits in the setup guide.

Check the source before the result

The evidence register links each claim to identity records, releases, primary source reviews and tests. The About page sets out the 5 working rules behind every tool.

Open the evidence register Maintained rates

The evidence supports limited claims about the software, not endorsements or client outcomes.