Every week, business owners pay for answers — in fees, in phone calls, in hours lost to ATO web pages — that a good calculator could give them free in about 60 seconds. How big will my refund be? What does a $75,000 employee actually cost me? Is the money I drew out of my company quietly becoming a tax problem? Questions like these don’t always need an appointment. They need a well-built tool with current Australian rates behind it.
So we built one for each of them. Trinity Accounting Practice now has 19 free accounting calculators for Australian taxpayers and business owners, all living at trinitygroup.com.au/tools. Every one of them is free, there’s no signup and no email gate, everything runs in your browser, and nothing you type is stored anywhere. Open one, get your answer, close the tab.
Here they all are, grouped by what you’re trying to work out.
Tax and personal finance calculators
These six answer the questions individuals, investors and contractors ask us most — usually in the week before they lodge.
Income Tax Calculator 2025/2026
For anyone lodging an Australian tax return who wants to know the answer before the ATO does. Enter your income and withholding, and it works out your refund or amount payable using the FY26 tax brackets, Medicare Levy, Medicare Levy Surcharge, HECS-HELP repayments and the Low Income Tax Offset. You get a clear estimate of where you’ll land — refund or bill — and what’s driving it.
Tax Deduction Finder by Industry
For employees and sole traders who suspect they’re leaving deductions on the table. Pick your occupation from more than 20 industries and it shows three lists: the deductions commonly claimed in your line of work, the ones people in your job often miss, and — just as valuable — the ones you shouldn’t claim. A practical pre-appointment checklist that can pay for your tax return several times over.
Super Salary Sacrifice Optimiser
For employees wondering whether salary sacrificing into super is worth it at their income. It calculates the tax saving on extra concessional contributions, tracks you against the FY26 $30,000 concessional cap, factors in any carry-forward cap room you may have, and warns you if Division 293 tax could apply at your income level. You get the net benefit in dollars, not in superannuation jargon.
Negative Gearing Calculator
For property investors — current and prospective — who want the real weekly number. It shows your rental property’s cash flow per week both before and after tax, the size of the negative gearing benefit, and the capital gains tax outcome under three different growth scenarios. The question it answers honestly: what is this property actually costing me to hold, and what might it return?
Logbook vs Cents-per-km Comparator
For anyone claiming car expenses who has ever wondered whether the logbook was worth the hassle. Enter your kilometres and running costs and it compares the two ATO car expense methods side by side, showing which one gives you the bigger deduction. Twelve weeks of logbook discipline either pays off or it doesn’t — this tells you before you start.
Contractor Calculator
For contractors weighing up a day rate against a salaried offer — or employees thinking about going out on their own. It converts a contractor day rate into its permanent salary equivalent (and back again), so you’re comparing like with like instead of being dazzled by the headline rate. Essential reading before you sign either kind of contract.
Running a business
Six tools for the questions that decide whether a business thrives, survives or gets a letter from the ATO.
Business Structure Comparison
For anyone starting a business, or wondering whether they’ve outgrown the structure they started with. It puts sole trader, partnership, company and trust side by side, comparing the tax treatment and asset protection of each. You get a clear picture of the trade-offs — which is exactly the homework worth doing before a structure conversation with your accountant.
Industry Benchmark Tool
For business owners who want to know how they stack up — not against a vague national average, but against FY2026 NSW benchmarks for their actual industry. Covering more than 20 industries, it compares your key numbers against the benchmark range and gives you traffic-light results: green where you’re healthy, red where you’re an outlier. Outliers are also what the ATO’s own benchmarking looks for, so this is worth five minutes of anyone’s time.
Cashflow Health Check
For owners who are profitable on paper but always feel broke. It scores your business across six cashflow ratios and then builds a 13-week cash forecast, so you can see the crunch coming while there’s still time to do something about it. The question it answers: is my cash position actually healthy, or just lucky so far?
Cash Flow Habits Scorecard
For owners who want to know whether the problem is the business or the habits. Ten quick questions diagnose your cash management discipline — invoicing speed, follow-up, buffers, forecasting — and score where you sit. It pairs naturally with the Cashflow Health Check above: one measures the numbers, this one measures the behaviour behind them.
Division 7A Loan Calculator
For company owners who have drawn money out of their company and need to keep the loan compliant. It calculates your minimum yearly repayment and builds the full amortisation schedule using the 8.37% FY2025-26 ATO benchmark interest rate. Division 7A mistakes are among the most expensive we see, and most of them start with nobody knowing the repayment number — this gives you that number in seconds.
Director Penalty Notice Risk Checker
For company directors — including anyone who became one without thinking much about it. It assesses your personal exposure to the company’s PAYG withholding, super and GST debts, and explains the difference between lockdown and non-lockdown director penalty notices, which determines whether you can still escape personal liability by acting. If you sit on any company’s board, this is ten minutes that could protect your house.
Employers and payroll
Two tools for the moment a business stops being just you.
True Cost-to-Employ Calculator
For any employer about to make a hire — especially the first one. It takes the salary you’re offering and adds what the payslip never shows: super, leave entitlements, workers compensation and payroll tax, with industry award presets to get the details right. The answer is the real annual cost of that employee, which is the number your hiring decision should actually be based on.
NSW Payroll Tax Calculator 2025-26
For growing NSW employers approaching — or unsure whether they’ve crossed — the payroll tax threshold. It applies the $1.2 million threshold and 5.45% rate, and handles the parts that catch people out: interstate wage apportionment and grouping rules that can combine related businesses’ wage bills. Payroll tax is the registration obligation employers most often discover late; this tool exists so you discover it early.
Industry-specific calculators
Five tools built for the sectors we work with every day — childcare, NDIS and construction — where the generic calculators simply don’t fit.
Childcare Profitability Calculator
For owners and operators of NSW childcare centres. It models your centre’s EBITDA, calculates your breakeven occupancy, and checks your staffing against ratio compliance requirements. The question every centre owner should be able to answer instantly: at what occupancy does this centre actually make money?
Childcare Staffing Wage Cost Calculator
For centre directors who suspect their roster is costing more than it should. Room by room, it calculates your wage variance above the NQF minimum ratios — showing exactly where you’re staffed beyond what compliance requires and what that generosity costs each week. Staffing is the biggest line in any centre’s budget; this shows you where it’s going.
Child Care Subsidy Estimator
For families — and for centres who want to help enrolling families understand their fees. It estimates a family’s CCS percentage, their subsidised hours, and the out-of-pocket cost that will actually hit their bank account. Centres tell us this conversation happens at every enrolment; now there’s a tool to point to.
NDIS Provider Margin Calculator
For NDIS providers who bill at price guide rates and still aren’t sure why the money disappears. It calculates your true margin per billable hour, using price guide rates on the income side and SCHADS Award costs on the expense side. Many providers discover their margin per hour is far thinner than they assumed — better to learn that from a calculator than from the bank balance.
Construction Project Profit Calculator
For builders and trades pricing their next project. It works out gross and net margin, loads up labour with its real on-costs, finds your breakeven point and accounts for retention — the money you’ve earned but can’t touch yet. The question it answers before you sign the contract: will this job actually make money, or just keep everyone busy?
Why a paying accounting firm gives all this away free
Fair question. Trinity Accounting Practice has been operating from Beverly Hills in Sydney since 2003, and as a Registered Tax Agent we’ve spent more than two decades answering the same client questions at the start of almost every meeting — what’s my refund looking like, what will this employee cost, is my structure right, why is there profit but no cash. These 19 calculators are those questions, turned into tools.
The honest commercial logic: a client who arrives having already run the numbers has a better meeting with us, and a business owner who finds these tools useful tends to remember who built them. There’s no catch beyond that. No signup, no lead-capture forms, no data harvesting — every calculator runs entirely in your browser and stores nothing.
Frequently asked questions
Are these calculators really free?
Yes — completely. There’s no payment, no signup, no email address required and no trial period. Every tool at trinitygroup.com.au/tools is free to use as often as you like, for yourself, your business or your clients.
Is my data stored anywhere?
No. Every calculator runs entirely in your browser. Nothing you type is sent to our servers, saved or stored anywhere — when you close the tab, the numbers are gone. That’s by design.
Are the rates current for 2025-26?
Yes. The tools are built on current-year figures — including the FY26 income tax brackets, the $30,000 concessional super cap, the 8.37% Division 7A benchmark rate and the NSW payroll tax threshold of $1.2 million at 5.45%. We update the calculators as rates change, and each tool states the year its figures apply to.
Do these calculators replace an accountant?
No — and we’d say that even if we weren’t one. The calculators give you accurate general estimates so you can understand your position and ask better questions. They can’t see your full circumstances, and they don’t constitute advice. Think of them as the start of the conversation, not the end of it.
Can I share these tools with my team or clients?
Please do. Every calculator has a public link, so you can send one to a business partner, your bookkeeper, an enrolling family or anyone else who’d find it useful. No account needed on their end either.
Bookmark the tools — then book the conversation
Save trinitygroup.com.au/tools now, and the next time a money question pops into your head at 9pm, you’ll have the answer before the kettle boils. And when a calculator shows you something that needs a human — a structure that doesn’t fit, a Division 7A loan with no repayment plan, a margin that’s vanishing — that’s the moment to talk to us.
Book a Free Strategy Call with the Trinity team →
General advice only. This article contains general information current as at June 2026 and does not constitute tax, financial or legal advice. The calculators referenced provide general estimates only and do not take into account your personal circumstances, objectives or needs. Before acting on any information or calculator output, you should consider its appropriateness to your situation and seek professional advice from Trinity Accounting Practice or another qualified adviser. Liability limited by a scheme approved under Professional Standards Legislation.