A small gap to free shipping is not, by itself, a reason to buy more. Compare the final payment for your necessary basket with the payment after adding an item. The calculator separates cash spent today from the possible benefit of replacing a planned future purchase.
Compare the checkout totals, not the free-shipping banner
A contains only what you need; B includes the extra items. Enter each final item total (after discounts, including taxes and mandatory charges) and its actual shipping charge in the same currency. Count each charge once. Shipping is not automatically set to zero.
Tool 1 · Compare two actual checkout totals
Compare two checkout totals
Enter the final goods amount and delivery charges from each checkout in the same currency. Differences are B minus A.
Amounts are calculated in your browser. Sharing puts the numbers and currency in the link, where recipients can see them. Existing page-visit statistics operate separately.
Compares actual checkout amounts in one currency. It does not decide shipping eligibility, exchange rates, product value, points or return costs.
Basket A contains only what you need. Basket B keeps those same necessary items and adds something else. Use the same delivery destination and method, then record the final goods total after discounts, taxes and mandatory charges, plus the delivery charge. Do not count a charge in both fields. If several sellers charge for delivery, add the actual delivery fees for each basket.
This comparison worksheet does not set delivery to zero when a threshold is reached. It adds goods A + delivery A and goods B + delivery B, then shows B minus A. A negative difference means B costs less at this checkout; a positive one means it costs more. Choose the same currency for both. No exchange-rate conversion is performed.
Hypothetical KRW figures: A contains 28,000 in goods plus 3,000 delivery, for a total of 31,000. If B contains 30,500 in goods and really has zero delivery, its total is 30,500, or 500 less. If a 1,500 delivery charge remains, B totals 32,000, or 1,000 more. The final checkout figures matter more than the banner.
Save a CSV to compare with the next checkout screen, or copy a shared link containing the numbers and currency. Anyone receiving the link can see the amounts. There are no fields for names, order numbers or addresses. A small difference is not a reason to add goods you have no plan to use. It cannot measure points, quality, storage space or a future refund.
The US FTC’s online shopping guidance also recommends checking the full cost, including delivery and taxes, and whether a deal requires unwanted purchases. We use that guidance to support the comparison method, not to apply US rules to transactions elsewhere. The existing threshold and planned-future-purchase calculator remains below.
Checked: 9 October 2026. Examples are hypothetical; no product test or first-hand purchase review is claimed.
Choose the calculator for the information you have
The two tools in this guide use different assumptions. First distinguish actual amounts from checkout screens from a hypothetical comparison under one free-shipping threshold.
- Tool 1 · Compare two actual checkout totals
Enter the final goods amount and actual delivery fees for A and B. This tool does not set delivery to zero merely because a threshold is reached.
- Tool 2 · Simulate a shipping threshold and a planned future purchase
This assumes one delivery charge and threshold apply to all the goods, with delivery for B becoming zero when the threshold is reached. Displaced future spending cannot exceed the added purchase cost; include only goods you had already planned to buy and will use. Subtracting that amount gives a longer-term comparison, not a reduction in today's payment or verified future savings.
For Tool 1, enter the final goods amount after discounts, taxes and mandatory charges, keeping delivery in its separate field. Do not count a charge in both fields. Tool 2 retains the entered delivery charge for A and uses goods cost plus added purchase cost directly as the qualifying amount. If the seller uses another basis, such as a pre-discount subtotal, this model cannot keep the qualifying amount separate from the payment amount: check the actual checkout and use Tool 1. Neither tool calculates coupon rules, tax rules or delivery charges after a return.
Do not add the two results together. If the actual checkout or seller's applicable terms differ from the assumptions, compare again using the actual conditions.
- Necessary basket: 28,000+3,000=₩31,000
- Add ₩2,500: pay ₩30,500
- Add ₩5,000: pay ₩33,000
- Save ₩500 today or spend ₩2,000 more
Replacing a planned future purchase does not reduce today’s payment.
Hypothetical KRW example with a ₩30,000 threshold and delivery genuinely reduced to zero after the addition.
Tool 2 · Simulate a shipping threshold and a planned future purchase
Calculate with your own numbers
Amounts use your chosen currency. A negative difference means a lower cost; a positive one means a higher cost.
This tool does not transmit your entries or store them on a server. The CSV is created in your browser. All sample numbers are hypothetical; use one currency and consistent units.
Compare two baskets under the same conditions
Basket A contains only what you need; basket B adds an item to qualify for free shipping. Use product totals after applicable discounts, taxes and required options. This simple model assumes one shipping charge and that all added items count toward the same threshold. It does not model separate sellers or product-specific delivery rules.
The cash difference is extra item cost + shipping for B − shipping for A. A negative difference means B costs less today. The calculator sets B's shipping to zero when the combined product total reaches the threshold. If a seller uses a different qualifying subtotal, check eligibility yourself before relying on the result.
The future-purchase replacement amount covers only the extra goods you already intended to buy and will actually use. Subtracting it gives a longer-term cost comparison, not a smaller payment today. Enter zero for uncertain purchases or points you may never redeem.
Worked example: a KRW 2,000 gap and a KRW 2,500 extra item
All amounts are hypothetical Korean won, not live prices or currency conversions. Necessary goods cost 28,000, shipping is 3,000 and the threshold is 30,000. Adding an item costing 2,500 makes A cost 31,000 and B cost 30,500: B is 500 cheaper today.
If the added item costs 5,000, B costs 33,000, or 2,000 more today. If all 5,000 genuinely replaces a later planned purchase, the longer-term difference is −3,000. Your current payment still rises by 2,000. Keep these two results separate when working within a spending limit.
Checks before payment
- Record the final goods total and shipping for the necessary basket.
- Check discount order and the subtotal used for shipping eligibility.
- Confirm the actual delivery charge on the final payment screen.
- Set future-purchase replacement to zero unless you have a realistic use plan.
- Check the seller's terms for shipping charges after partial returns.
A lower calculated cost is not a requirement to buy
The tool does not assess storage, product quality, expiry, return fees or remote-area surcharges. Points are not automatically equivalent to cash. If the checkout screen differs from the model, use the actual checkout terms and recalculate.
Common questions
Can I enter just the gap to the threshold?
No. An available extra product may cost more than that gap. Enter the total price of the items you would actually add.
Do points make adding an item worthwhile?
Check redemption restrictions and expiry separately. Do not count the displayed points value as guaranteed cash savings.
Sources and how this guide was written
Durudam prepared this calculation and record-keeping guide with AI assistance. It does not claim product testing or on-location reporting. Examples are hypothetical; formulas and assumptions are disclosed. Sources checked: 4 October 2026.
Related reading
What to check next in this situation
- Are Refills Better Value? Compare Cost Per Use, Not Just Volume
If the extra item is a refill, compare the recommended dose and any container cost as well as package volume.
- What Will an Online Return Really Cost? A Refund Worksheet
If you might return part of the order, record deductions from the refund separately from return postage paid elsewhere.
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