Free tool · GST ready · No sign-up
Break-even ROAS calculator for Australian stores
Put in what an order is worth and what it costs you to fill. You'll see the return a first order needs to break even after GST, postage and fees, the return you need to keep a margin, and what a month looks like at your ad budget.
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Made-up example numbers. Change any field.
Where to find your numbers
- Order value: your average order over the last 90 days, from Shopify analytics.
- Postage: what your carrier actually charged you per parcel, packaging included.
- Payment fees: the rate on your payment provider's statement, including buy now, pay later.
Break-even ROAS
Sales, incl GST, for every A$1 of ad spend before a first order stops losing money.Target ROAS
Keeps 10% of the ex-GST order value after ads. Max cost per purchase at that margin: A$35.27.Max cost per purchase
Pay Meta more than this to win an order and that order loses money.Contribution per order
What's left from the ex-GST order value after product, postage, fees and other costs. 49% of it.Every order loses money before a dollar goes to ads. Fix the price or the costs first.
GST = order value ÷ 11 · fee charged on the full order value · A$9.00 GST in this order
A month at A$3,000 of ad spend
Illustrative, worked from your inputs. Not a forecast.
| If Meta returns | Sales, incl GST | Orders | Left after ads |
|---|---|---|---|
| 2.00x | A$6,000 | 61 | -A$317 |
| 2.24x break-even | A$6,709 | 68 | A$0 |
| 2.81x your target | A$8,421 | 85 | A$766 |
| 3.00x | A$9,000 | 91 | A$1,024 |
| 4.00x | A$12,000 | 121 | A$2,366 |
Left after ads is what those orders contribute, less the ad spend. Wages, rent, software and any agency fee still come out of it.
How it works
The maths, in plain words
Five steps, in the order the calculator does them. It's the first sum I do when I audit an ad account, because a ROAS target means nothing until you know this number.
Take the GST out
A GST-inclusive price carries one eleventh GST, so the part you keep is the order value divided by 1.1. Not registered for GST? Untick the box and the whole order value counts.
Work out the payment fee
Card and wallet providers charge on the full amount the customer pays, GST included, so the fee is worked on the inclusive order value.
Subtract the cost of filling the order
Product cost, postage, the fee, and anything else you pay per order: packaging, pick and pack, per-order app charges. If you claim GST credits on those costs, enter them ex GST. What's left is your contribution per order.
Divide to get break-even ROAS
GST-inclusive order value divided by contribution. We use the inclusive value because Meta's purchase value is usually what the customer paid, so you compare like with like. Check what your store actually sends to Meta.
Set your margin, then look at the month
For a target ROAS, put aside the margin you want to keep and divide again. For the month, your budget times a ROAS gives sales, sales divided by the order value gives orders, and what those orders contribute less the spend is what's left.
Worked example · made-up numbers
One A$99 order, start to finish
These are the numbers the calculator loads with. Read the result this way: this store can pay Meta up to its full contribution per order to win a first order and still not lose money on it.
Below that break-even return, every new order costs more to win than it brings in. At 2x, the same A$3,000 month goes backwards by about A$317, before anyone buys a second time. At 3x it leaves about A$1,024 to cover everything else in the business.
Notice where the money goes. Postage alone takes more than a tenth of the order. That's why the fastest fix is often the order value, not the ads.
| Step | Amount |
|---|---|
| Order value, incl GST | A$99.00 |
| GST, one eleventh | A$9.00 |
| Order value, ex GST | A$90.00 |
| Less product cost | A$30.00 |
| Less postage to you | A$12.00 |
| Less payment fee, 1.75% of A$99 | A$1.73 |
| Less packing and apps | A$2.00 |
| Contribution per order | A$44.27 |
| Break-even ROAS, 99 ÷ 44.27 | 2.24x |
| Keep 10% of A$90 after ads | A$9.00 |
| Target ROAS, 99 ÷ 35.27 | 2.81x |
What to do with your number
Pick the lever that moves it
Your break-even is the floor. How far above it you can run depends on the order value, the costs and whether Meta's numbers are real.
Bundles, add-ons near the cart and per-serve pricing. The cheapest way to lower the return you need.
Postage eating it?Set a free-shipping lineHow to pick a threshold your margin can carry, and get customers aiming for it.
Meta says you're above it?Check it against the storeDuplicates and test orders can make a losing month look fine. Reconcile before you scale.
Comfortably above?Find more ads that sellTest statics against video and move budget to whatever the store confirms.
Order value moves this more than anything
Two stores we've worked on sit at opposite ends of the scale. One had an A$8.85 hero product, the other sells a considered purchase in the thousands. Products from under A$9 to A$1,699. Same system. What changes is the return each one needs, and that's why we start every account with this sum.
Average order
A$80
On an A$8.85 hero product
Rick Grant's Gluten Free. Store orders, first four days on the rebuilt store, 17 to 20 Aug 2026, no ads running.
Average order
A$1,601
Meta-attributed
Nuracom. 20 Apr to 29 Jul 2026.
Case study results. Outcomes vary.
All case studiesWhere it stops
What this calculator leaves out
It answers one question well: what does a first order need to return? Four things sit outside it.
- Repeat orders. A first order at break-even can still be a good buy if customers come back. If you have the repeat data, you can accept a lower first-order return. If you don't, plan on the first order paying for itself.
- Discounts, returns and refunds. Take your average discount off the order value, and add a returns allowance to the other costs.
- Fixed costs. Wages, rent, software and our fee sit outside the sum. The "left after ads" line has to cover them.
- Reported sales. Meta's ROAS is Meta's view of what it caused. We check it against the store before a dollar more goes in.
Want a second opinion?
I'll run these numbers on your real orders.
Give us access to your Ads Manager and store, and the free audit starts with this sum on your actual order values, postage and fees. Then you get your Scaling Roadmap: what's leaking and what we'd fix first.
Straight answers
ROAS questions we get
Anything else, call Jed on 0400 463 257.
What is a good ROAS for an Australian online store?
There isn't one number. A good ROAS is one comfortably above your own break-even, and that depends on order value, product cost and postage. A store with big orders and healthy margins can grow at a return that would sink a store selling cheap single items. Work out your break-even first, then set the target.
Should I compare this to Meta's ROAS or my store's numbers?
Your store's. Meta's reported return usually runs higher than what the store confirms, because of attribution windows, duplicate purchase events and orders other channels also claim. We scale on sales the store has actually banked.
Does the calculator handle GST?
Yes. It assumes your prices include GST and takes one eleventh out before working out what you keep. Untick the box if you're not registered for GST. If you claim GST credits on your costs, enter those costs ex GST.
Why does max cost per purchase equal contribution per order?
Because at break-even, everything the order contributes goes to Meta. Pay more than that to win the order and it loses money. Setting a margin to keep lowers the amount you can afford, and the calculator shows that figure under the target ROAS.
Does it work for Google Ads too?
Yes. The maths is the same for any channel that reports sales against spend. Depending on how tracking is set up, Google's conversion value can include or exclude GST and shipping, so check what your store sends before you compare.
Free audit, then your Scaling Roadmap
It's time to get Scaled.
Fill in a few details and I'll go through your ads, your website or store, and how you follow up enquiries, then show you what's leaking and what we'd fix first. If we're not a fit, no worries at all. You'll still leave with something you didn't know before.
Jed Lynham
Jed calls you personally, usually the same business day.
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