Free · nothing gated
Free eCommerce tools and calculators
Three working calculators that answer the questions most stores get wrong: what return on ad spend you actually need to break even, what your abandoned checkouts are worth, and what ACoS you can afford on Amazon. Every formula is printed on the page, and nothing asks for an email.
TOOLS LIVE
Three
COST
Free
EMAIL REQUIRED
No
FORMULAS SHOWN
All of them
A calculator is only useful if you can see what it assumed. Each of these shows the formula and states its limits.
- Why these three
Calculators that argue with you
Most free tools online exist to capture an email. These exist because three specific numbers get misread often enough to cost real money.
A return-on-spend figure means nothing without the margin behind it. An abandonment rate means nothing without the revenue behind it. An ACoS target means nothing without the contribution margin behind it. In each case the number everyone reports is the one that does not decide anything.
So each of these takes the inputs people usually leave out, prints the formula it used, and tells you what it has assumed. Where a tool cannot know something — your true landed cost, your refund rate — it says so rather than quietly defaulting it to zero.
- No email, no signup, no results held back behind a form
- The formula printed under every calculator
- Assumptions and limits stated, not buried
- Nothing sent anywhere — the maths runs in your browser
- The tools
Three calculators, live now
Each one sits next to the glossary or statistics page that explains the number it produces.
PAID MEDIA
Enter your gross margin and find the return on ad spend you have to beat before a campaign makes money rather than revenue.
CONVERSION
Sessions, abandonment rate and average order value in — the revenue at stake, and what a realistic improvement is actually worth.
MARKETPLACE
Your Amazon break-even advertising cost of sale, after referral fees and FBA, plus what it means for a TACoS target.
- Before you start
Four numbers worth getting right first
Every calculator here is only as honest as what you put into it. These four are the ones people estimate badly.
Gross margin, after everything
- Selling price minus landed cost, not minus invoice cost
- Include duty, freight inbound and payment processing
- Use the blended figure for the range the ads actually push
What delivery really costs you
- Carriage and packaging per order, not per parcel rate card
- Weighted for the zones your orders actually travel to
- Include the free-delivery orders in the average
Your refund and return rate
- Measured as a share of units shipped, not of revenue
- Split by category if one range distorts the blend
- Leaving this at zero flatters every result on this page
A conversion rate you trust
- From analytics that reconciles to your store within about 5%
- Measured on the traffic the calculation is about
- If it does not reconcile, fix that before modelling anything
If two or more of these are guesses, the growth assessment is a better use of forty minutes than any calculator.
- Limits
What these tools will not do
A calculator that pretends to more certainty than the inputs allow is worse than no calculator.
Account for lifetime value
Every figure here is first-order. A campaign below break-even on the first purchase can still be right if the second purchase is reliable — but that is a cohort question, not a calculator question.
Resolve attribution
The numbers you feed in come from platforms that each claim the same sale. These tools do the arithmetic honestly; they cannot fix a measurement layer that double-counts.
Model incrementality
Spend you would have converted anyway is still counted as spend that worked. Only a holdout answers that, and none of these run one.
Handle catalogue spread
A blended margin across a catalogue with a three-to-one spread produces a blended answer. If your range is that wide, run each calculator per margin tier instead of once.
Store anything
The maths runs in your browser. Nothing is sent to us, nothing is saved, and closing the tab clears it. That is also why there is no email field.
Each tool repeats its own specific limits underneath itself, so nobody has to come back to this page to find them.
- In production
What is coming next
Named here so you know what exists and what does not. None of these are linked, because none of them are built yet.
ASSESSMENT
Interactive growth assessment
A scored version of the twelve-point framework, using exactly the thresholds already published on the assessment page.
In production — not yet published
MARGIN
Contribution margin per order
Price, cost, carriage, fees and returns in — what you actually keep per order out.
In production — not yet published
PAID MEDIA
Shopping feed budget split
Splitting spend across margin tiers rather than one blended target for the whole catalogue.
In production — not yet published
CONVERSION
A/B test duration and confidence
How long a test needs to run at your traffic before the result means anything.
In production — not yet published
When one of these goes live it appears in the section above with the formula printed, the same as the other three.
- Questions
Tools FAQs
What people ask before trusting a number a website gave them.
Do I have to give you an email?
No. There is no form, no gate and no results held back. The calculation runs in your browser and finishes on the page you are already on. If a free tool asks for an email before showing a result, the tool is the lead magnet rather than the point.
Is my data sent to you?
No. Everything runs client-side in JavaScript, nothing is transmitted, and nothing is stored. Close the tab and it is gone. We could not see your margins even if we wanted to.
How accurate are the results?
The arithmetic is exact. The answer is only as good as the inputs, which is why each tool prints its formula and lists what it assumes. Feed it a margin that ignores carriage and it will confidently tell you the wrong thing.
Why is break-even ROAS different from my target ROAS?
Break-even is where a campaign stops losing money on the sale. A target is break-even plus whatever profit you need. Most accounts optimise toward a target that was set before anyone checked where break-even actually was — the ROAS definition covers why.
Can I use these for a whole catalogue at once?
Only if your margins are reasonably uniform. Across a catalogue with a wide spread, a blended input gives a blended answer that is wrong for both ends. Run the calculator once per margin tier instead.
Do these account for repeat purchases?
No, deliberately. Everything here is first-order, on the first sale. Lifetime value changes the picture and is a cohort question rather than a calculator question — ask about it on a strategy call.
Can I embed these on my own site?
Not currently. If that would be useful, say so and we will look at it — the maths is not the valuable part and we would rather it was used than hoarded.
Where do the benchmark figures come from?
Any benchmark used as a default is cited on our statistics pages with its original source, year and sample. Nothing here uses a number we cannot point at.
- Elsewhere in resources
Four other branches
The tools tell you the size of a problem. These help you do something about it.
CHECKLISTS
Working checklists for SEO, conversion and Amazon listings, each check stating the action first and the reason second.
TEMPLATES
Actual downloadable files with working formulas — not articles with the word template in the title.
STATISTICS
Every figure carrying its original source, publication year and sample, so you can check it rather than trust it.
The calculator found the number. Now what?
If a result here surprised you, that is usually the constraint showing itself. The free audit puts evidence behind it in five working days, or run the twelve-point assessment yourself in forty minutes.