Flat Rate vs Calculated Shipping Calculator
Which pricing model costs you less.
Calculated is cheaper
$9.04
$0.61 per order difference
Flat rate wins on heavy parcels going far; calculated wins on light parcels going a short distance. Rules that pick per order capture both.
How the Flat Rate vs Calculated Shipping Calculator works
Flat rate ignores weight and distance within its limits, which makes it excellent for heavy parcels travelling far and poor for light ones going next door. Calculated shipping is the reverse. Which wins depends entirely on the shape of your actual order mix.
Not financial advice. Marketplace fees change, and they vary by country, plan and seller status. Every rate here is an editable default, not a quoted price — check the platform's current fee schedule before you price a product against it. This is not tax or business advice.
Frequently asked questions
When does flat rate win?
Heavy items, long distances, and consistent parcel sizes that fill the box. If your typical parcel is dense and crosses several zones, flat rate is usually cheaper and far simpler to quote.
When does calculated win?
Light parcels, short distances, and highly variable order sizes. Paying a flat rate to send a 200 g item to the next town wastes most of what the flat rate buys.
Can I use both?
Yes, and most sophisticated setups do — rules that select flat rate above a weight threshold and calculated below it. The complexity is worth it once shipping is a material share of cost.
What about a single flat fee to customers?
That is a pricing decision rather than a carrier one. Charging every customer £4.95 while your actual cost varies means you subsidise distant heavy orders from nearby light ones — fine if the average works, expensive if your mix shifts.