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Quantity break calculator

Enter your unit price, unit cost and up to four tiers to see what each quantity break charges per unit, what it earns per order, and whether it beats the profit of selling one unit at full price.

Calculator

The regular price of one unit.

What one unit costs you.

Tiers (up to 4, leave a row empty to skip it)

Tier 1
Tier 2
Tier 3
Tier 4

"Total price" is the price for the whole tier, such as 2 for $45.

Results

  1. 1 unit at full price

    Baseline
    Unit price
    $24.99
    Total
    $24.99
    Profit
    $17.49
    Margin
    70%

    Every tier below is compared with this single sale.

  2. Tier 1: 2 units, 10% off

    Beats 1 unit
    Unit price
    $22.50
    Total
    $45.00Saves $4.98 (10%)
    Profit
    $30.00+$12.51 vs 1 unit
    Margin
    66.7%

    Beats 1-unit profit: yes. It takes 2 units at this price, 1 more than a single sale.

  3. Tier 2: 3 units, 15% off

    Beats 1 unit
    Unit price
    $21.25
    Total
    $63.75Saves $11.22 (15%)
    Profit
    $41.25+$23.76 vs 1 unit
    Margin
    64.7%

    Beats 1-unit profit: yes. It takes 2 units at this price, 1 more than a single sale.

  4. Tier 3: 4 units, 20% off

    Beats 1 unit
    Unit price
    $20.00
    Total
    $80.00Saves $19.96 (20%)
    Profit
    $50.00+$32.51 vs 1 unit
    Margin
    62.5%

    Beats 1-unit profit: yes. It takes 2 units at this price, 1 more than a single sale.

Percentage tiers are rounded the way Shopify rounds them: the discount on each unit is rounded down to the cent.

Your numbers stay in your browser: nothing is sent or saved. The link keeps your inputs, so you can bookmark or share it.

How it works

The math, step by step

1. Price per unit. For a percentage tier, the discount on one unit is the price × the percentage, rounded down to the cent. That is how Shopify rounds it in our tests on live carts. For an amount off, it is the price minus the amount. For a total price, it is the total ÷ the quantity.

2. Total, profit and margin. The total is the unit price × the quantity. Profit is the total minus the cost of the units. Margin is profit ÷ total.

3. Does the tier pay? The simplest sale is one unit at full price, which earns the price minus the cost. At a tier's lower unit price, each unit earns less. The calculator finds how many units the shopper must buy at that price for the order to earn more than that single sale, and checks whether the tier's quantity gets there.

What it leaves out. Shipping, fees and ad costs. They are paid once per order, so leaving them out understates what a bigger order earns. And whether shoppers pick the tier at all: that is for your store's own data.

Formulas

  1. Percentage tiers: discount per unit = price × % off, rounded down to the cent (how Shopify rounds it)
  2. Unit price = price - discount per unit
  3. Total = unit price × quantity
  4. Profit per order = total - unit cost × quantity; margin = profit ÷ total
  5. Units to beat one full-price sale = the smallest whole number n where n × (unit price - unit cost) > price - unit cost

Worked example

One store, start to finish

  1. The product

    A serum at $24.99 that costs $7.50 to make. The tier: buy 3, save 15%.

  2. One unit

    $24.99 - $7.50 = $17.49 profit, a 70% margin.

  3. Discount per unit

    $24.99 × 15% = $3.7485. Shopify rounds the discount down to $3.74, so each unit costs $21.25 (not $21.24).

  4. Total and profit

    $21.25 × 3 = $63.75. Profit $63.75 - 3 × $7.50 = $41.25, a 64.7% margin.

  5. Beats 1-unit profit?

    Each unit now earns $21.25 - $7.50 = $13.75. One unit ($13.75) earns less than a full-price sale ($17.49), two units ($27.50) earn more. So the tier beats a single sale from 2 units, 1 more than a single sale. It sells 3, so yes.

Open this example in the calculator

Put the tiers on your product page

Tiers that show the saving.

  • BundleUp · Product page

    BundleUp shows quantity tiers in the Add to cart area of your product page, with the price per unit and a "You save" line, and applies the discount through one automatic Shopify discount. Tiers can be a percentage, a fixed amount per unit or a fixed price per offer.

    About BundleUp Shopify App Store

FAQ

Quantity breaks questions

What is a quantity break?
A lower price per unit when a shopper buys more of the same product, such as buy 2 and save 10%, buy 3 and save 15%. Each step is a tier.
How does Shopify round percentage discounts?
In our tests on live Shopify carts, Shopify works out a percentage discount per unit and rounds the discount down to the cent. $24.99 at 15% off is a $3.7485 discount, which becomes $3.74, so each unit costs $21.25 rather than $21.24. The calculator rounds the same way, so its totals match the cart.
How big should each tier's discount be?
Big enough that the shopper notices, small enough that the order still earns more than a single sale. Watch the profit column: each tier should make more per order than one unit at full price, and the units-to-beat number should be at or below the tier's quantity.
What does "beats 1-unit profit" mean?
It compares the tier with the simplest sale: one unit at full price. At the tier's discounted unit price, each unit earns less, so the shopper has to buy enough units for the order to earn more in total. The calculator shows that number of units, and whether the tier's quantity reaches it.
Should I use a percentage or an amount off?
The math is the same. A percentage scales with the price, an amount off each unit stays fixed, and a set price for the tier reads well on the page (2 for $45). Only percentage discounts get Shopify's rounding; amounts and set prices are exact.
Can I set these tiers up in BundleUp?
Yes. BundleUp tiers take a percentage, a fixed amount per unit or a fixed price per offer, and BundleUp applies them through one automatic Shopify discount, so shoppers don't need a code.

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