Quick guide
How to use this calculator
- Enter values from one real situation and keep currencies, quantities, and periods consistent.
- Use the optional fields only when they apply; the calculator will keep every entered adjustment visible in the result.
- Compare the component outputs and read the calculator-specific boundary before making a purchase or plan.
Calculation method
Calculation method
Checkout total = quantity × unit price × (1 − discount rate) − fixed coupon + delivery + tax on the selected taxable subtotal; entered discounts may not exceed merchandise value.
Entered fixed decimals use exact rational arithmetic wherever the task involves money, ratios, or allocations. Whole packages, tables, seats, and items round only where the real task requires indivisible units.
Worked example
Worked example
Two items at 50 with 20% off, a 5 coupon, 4 delivery, and 10% tax on discounted merchandise total 86.50.
Checkout total = quantity × unit price × (1 − discount rate) − fixed coupon + delivery + tax on the selected taxable subtotal; entered discounts may not exceed merchandise value.
Supported inputs
Precision and limits
Your scenario
No live price, promotion, retailer policy, tax, cultural norm, household consumption rate, attendance rate, or media speed is supplied automatically.
Plan, not a guarantee
Results organize visitor-entered assumptions. They do not guarantee availability, attendance, product life, savings, suitability, or contractual rights.
Precision and privacy
Inputs stay in this browser. Invalid denominators, contradictory counts, impossible percentages, and unsupported ranges return explicit messages rather than misleading results.
Calculator-specific boundary
The calculator applies percentage discount before the fixed coupon and applies tax to discounted merchandise after the coupon. Local tax and promotion rules may differ.
Continue calculating