Free pricing math · shopmarginbase.com

Price it so you actually keep something.

Markup, marketplace fees, break-even, reverse sales tax — the arithmetic shop owners redo on paper or in a half-finished spreadsheet. Type the numbers; we do the dividing.

Nothing is uploaded. Close the tab and the inputs are gone. These are estimates for planning, not tax or accounting advice.

Runs in your browser  ·  No signup  ·  Not tax advice

The ones people open first

Thirty calculators are live. These six cover the questions that show up before a price tag, listing, or menu reprint.

6 featured
  1. 01Markup calculator
  2. 02Reverse sales tax
  3. 03Etsy fees
  4. 04Break-even point
  5. 05Product pricing
  6. 06Shopify profit

See all 30 calculators →

Find it by the job you're doing

Not a feature matrix — groups for the work in front of you: pricing a SKU, covering fixed costs, splitting tax, or checking what a marketplace leaves.

Markup & margin

Markup is profit over cost. Margin is profit over price. Same dollars, different denominator — these tools keep the two from getting swapped on the sales floor.

Markup·Margin·Markup vs margin·Keystone

all markup & margin

Break-even

Rent and software don’t wait for a busy week. Plug in fixed costs, price, and variable cost; see how many units (and dollars) cover the month.

Break-even units·Break-even revenue·Fixed vs variable·Contribution margin

all break-even

Pricing & food cost

Shelf price from a target margin, or food cost % from plate cost and menu price. Useful before you reprint tags or the next menu.

Product pricing·Food cost %·Recipe cost·Menu price

all pricing & food cost

Sales tax

We don’t look up your ZIP or scrape a rate table. You enter the rate you already use; we add tax onto a price or pull it out of a gross total.

Add sales tax·Reverse sales tax·Tax by rate·Total from subtotal

all sales tax

Fees & marketplace

Etsy, Shopify, and FBA nick every sale differently. These are estimates with common defaults — your seller dashboard is the source of truth.

Etsy fees·Shopify profit·Amazon FBA

all fees & marketplace

What this site is (and isn't)

01 The math is grade-school arithmetic with shop labels: markup vs margin, fee stacks, break-even units. There is no growth framework, no dashboard, and no account to create.

02 Inputs stay in your browser. We don't store costs, prices, or fee assumptions on a server. Refresh or close the tab and they're gone.

03 Fee and tax tools use rates youenter (or common defaults you can override). Marketplace dashboards and your state's rules win when numbers disagree. This is for planning a price — not filing taxes or reconciling books.

Estimates only — not tax, accounting, or legal advice.