Discount Calculator
See the discount in dollars and the new sale price.
Last updated: January 2025 · Built for the 2024–25 financial year
Inputs
Results
You save
$49.75
Sale price
$149.25
Results are estimates only. For financial advice, consult a licensed adviser.
Overview
Sale price, savings and effective discount
Retail discounts in Australia are applied to the GST-inclusive ticket price under ACCC pricing guidance. A '30% off' tag must reduce the labelled price by 30%, not the pre-GST amount.
Stacked discounts — like '20% off, then a further 10% at checkout' — multiply rather than add. The effective discount is 1 − (0.80 × 0.90) = 28%, not 30%.
Formula
Discount maths
savings = price × (discount% / 100) sale price = price − savings original = sale ÷ (1 − discount%/100)
Worked example
$199 jacket, 25% off
- Savings = 199 × 0.25 = $49.75.
- Sale price = 199 − 49.75 = $149.25.
- If a further 10% applies: 149.25 × 0.90 = $134.33 (effective 32.5% off).
Answer: $149.25 → $134.33 with stacked promo
Pro tips
- •Always check the unit price for grocery 'multi-buy' deals.
- •Black Friday averages 25% off RRP — boxing day clears 40-60%.
- •Compare against camelcamelcamel-style price history.