BusinessVIDEO GUIDE
Profit margin vs markup: a 100-cost worked example
Compare margin and markup on a cost of 100 and a price of 150. Calculate the selling price needed for a target margin and include extra costs.
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Free tools for everyday commerce calculations. Articles and videos that explain the thinking behind them.
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All calculators ↗01 / ↗
Marketplace commission calculator
Work out commission, service fees, VAT and what actually lands in your account on a marketplace sale.
Open calculator ↗02 / ↗Volumetric weight calculator
Convert parcel dimensions to volumetric weight and see which figure your courier will actually bill.
Open calculator ↗03 / ↗Profit margin calculator
Turn cost and selling price into margin and markup, and stop confusing the two.
Open calculator ↗04 / ↗VAT calculator
Add VAT to a net amount or strip it out of a gross one, both directions at once.
Open calculator ↗05 / ↗Break-even calculator
Find how many units you need to sell each month before fixed costs are covered.
Open calculator ↗The thinking behind the numbers.
All notes ↗
Business2026-09-13 · 2 min read
Break-even point: how many sales cover your costs?
Calculate contribution and break-even units with fixed costs of 30,000. See how variable costs, rounding and daily targets change the result.
2026-09-13 · 3 min read
Profit margin vs markup: a 100-cost worked example
Compare margin and markup on a cost of 100 and a price of 150. Calculate the selling price needed for a target margin and include extra costs.
Business2026-09-13 · 2 min read
VAT-inclusive and exclusive prices: formulas and examples
Learn how to add VAT or extract it from a total using 1,000 and 1,200 examples, and avoid subtracting the rate from a VAT-inclusive price.
Business2026-09-13 · 2 min read
Marketplace fees: revenue, payout and profit explained
Follow a 1,200-unit sale through commission, shipping, service fees and VAT. Understand why a marketplace payout is not the same as profit.
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