Seller Math

How Many Sales to Break Even

Fixed costs do not care about your favorite platform. Here is the unit math that does.

Updated September 2026 · Estimates only

Break-even is not “when revenue equals product cost.” It is when contribution after variable fees and COGS has paid for the fixed costs you chose (apps, photography, plan fees, samples, portion of ads tested as fixed).

The formula that matters

Contribution per unit = Price − variable platform fees − product cost − variable shipping you pay

Units to break even = Fixed costs ÷ contribution per unit

If contribution is $8 and fixed costs this month are $240, you need 30 units before you are truly covering those fixed costs — not “30 units sold” in a vanity sense.

Example

Price $32 · fees ~$5 · COGS $12 · ship you pay $3 → contribution = $12

Fixed: Shopify plan slice + apps + packaging test = $180

Break-even ≈ 180 ÷ 12 = 15 units

Same product on a heavier-fee channel with $6 contribution → 30 units. Platform choice changes the finish line.

What to count as fixed vs variable

  • Variable: referral %, payment %, per-order fulfillment, unit COGS, outbound shipping per order.
  • Fixed (for the period): monthly software, studio rent share, minimum ad tests you will run anyway, batch photography.

Mislabeling ads as always fixed or always variable will fool you. Be consistent for the period you are planning.

Use with other tools

  1. Get contribution from Etsy, Amazon, or the comparator.
  2. Plug contribution + fixed costs into break-even.
  3. If units required are unrealistic for your traffic, change price, channel, or fixed spend — not your spreadsheet hopes.

Frequently asked questions

Does break-even include my salary?

Only if you put a salary (or owner draw) into fixed costs for the period. Otherwise you only covered software and product-related fixed spend.

What if contribution is negative?

You cannot break even by selling more. Fix price, fees, or COGS first.

Is this the same as ROI?

No. Break-even is the unit count to cover fixed costs. ROI compares profit to capital invested.