About Smart Logistics Calc

Smart Logistics Calc makes free calculators for the costs that decide whether an online store makes money: shipping, importing, fulfillment, inventory and marketplace fees.

Why this site exists

Many ecommerce cost tools either hide their formulas or quietly bake in rates and fees that are out of date by the time you use them. We take the opposite approach: you enter the rates from your own contracts and fee pages, and every result shows exactly how it was calculated, so you can check it and explain it to anyone.

Our principles

• No invented numbers. We do not ship carrier prices, marketplace fees or duty rates that we cannot keep verified.
• Transparent maths. Each calculator page documents its formula, a worked example, how to read the result and its limitations.
• Private by design. Calculations run in your browser. What you type is not sent to a server.
• Estimates, clearly labelled. Results are planning tools, not quotes or professional advice.

How the calculators are built and tested

Each calculation is a separate, documented function with automated tests covering normal inputs, zero values, boundaries, invalid input and unit conversions. Money is calculated in whole cents with a single, documented rounding rule so totals always match their line items. Unit conversions use exact international definitions (for example 1 lb = 0.45359237 kg).

The calculators

• Dimensional Weight Calculator - Find the dimensional and billable weight of a box using any carrier divisor and unit.
• Shipping Cost Calculator - Estimate a parcel’s cost from your rate card, with fuel and delivery surcharges itemized.
• Landed Cost Calculator - Add freight, duty, import tax and fees to supplier cost to get a true cost per unit.
• US Import Duty & Tariff Calculator - Add HTS duty, Section 301/232 tariffs, MPF and HMF to see what a US import really costs.
• 3PL Fulfillment Cost Calculator - Turn a 3PL price sheet into a monthly bill and cost per order, and compare up to three.
• Shopify Profit Margin Calculator - See what an order really earns after fees, shipping, returns and ads, and your break-even CPA.
• Amazon FBA Fee & Profit Calculator - Estimate FBA profit per unit and break-even price from the fees you enter.
• Inventory Carrying Cost Calculator - Measure what it costs per year to keep stock on the shelf, in money and as a %.
• Shipping Insurance Cost Calculator - Estimate the premium for insuring a parcel and its cost as a % of declared value.

How the site is funded

The site is free to use and is supported by advertising. Ads are labelled and kept apart from calculator controls and results. Advertisers have no influence over the content or the calculations.

Who runs it

Smart Logistics Calc is built and run by Raúl Vaquerizo Tortosa, based in Spain. I have worked in logistics for three years, in the IT side of the sector, optimizing processes and reducing operating costs. This site turns the cost calculations used in day-to-day logistics work into free tools that any online seller can use and check.

You can find my professional background on LinkedIn. Found a mistake or have an idea for a calculator? Please get in touch.