Where every number comes from
This page exists because the alternative is asking you to take our word for it. Every published rate this site uses appears below with its source, the date it took effect, the date we last read it, and an honest assessment of how well we can stand behind it.
Last review pass: Tue, 18 Aug 2026. Found something out of date? Tell us — corrections get published with the date they were made.
What the confidence levels mean
Primary source 13 sources
Read directly from the organisation that sets the rate.
Corroborated 8 sources
Three or more independent sources agree, but we have not seen the issuer publish it.
Secondary source 11 sources
One or two third-party reports. Treat as a starting point and check your own account.
Unverified 0 sources
We could not confirm this. It is never used as a silent default — you have to enter it yourself.
Nothing marked unverified is ever used as a silent default. Those figures are offered as editable inputs, switched off by default, with a warning attached — because a number you can see and question is worth more than a number that quietly makes your answer wrong.
The full register
| Source | Publisher | Effective | Checked | Confidence |
|---|---|---|---|---|
| DMM 113.1.3 — dimensional weight, and Notice 123 price list Read directly off the Domestic Mail Manual, revision 7-12-26. It states the divisor as 139, applies dimensional weight only to parcels exceeding one cubic foot (1,728 cubic inches), requires each measurement to be rounded up to the nearest whole inch before multiplying, and requires the result to be rounded up to the next whole number. Nonrectangular parcels multiply the cubic dimensions by 0.785 first. Notice 123, effective the same date, confirms the threshold and the 108-to-130 inch oversize band. | USPS Postal Explorer | 2026-07-12 | 2026-08-18 | Primary source |
| Notice 123 — Price List The complete published USPS tariff. Six tables are parsed directly from it — Ground Advantage, Priority Mail and Priority Mail Express, each in retail and commercial, 431 weight bands in total — and every row was checked for nine zone prices, prices that never fall as zone or weight rises, and the exact set of weight bands with nothing missing and nothing invented. Commercial was additionally verified to undercut retail at every comparable band. The PDF itself is kept in the repository and its SHA-256 recorded next to the numbers, so a reader can check them against the same document we read. USPS is the only major carrier that publishes its full rate card openly, which is why it is the only one we quote a price for. | USPS Postal Explorer | 2026-07-12 | 2026-08-18 | Primary source |
| Parcel size, weight and fee standards Combined length and girth: 108 inches maximum for most services, 130 inches for USPS Ground Advantage. Between 108 and 130 inches the parcel is priced as oversize. | USPS | — | 2026-08-17 | Primary source |
| UPS fuel surcharge tables Fuel surcharges reset weekly against a published diesel-price bracket table. Any calculator that hardcodes a percentage is stale within days, which is why ours takes the current fuel price as an input. | UPS | — | 2026-08-17 | Primary source |
| Volumetric weight formula for Indian couriers Indian domestic couriers bill L × W × H in centimetres divided by 5000. | Shiprocket | — | 2026-08-17 | Primary source |
| Suspending duty-free de minimis treatment for all countries Signed 2025-07-30, effective 2025-08-29, applying to all countries rather than only China and Hong Kong. The $800 exemption that most duty calculators still assume no longer exists. | The White House (Executive Order 14324) | 2025-08-29 | 2026-08-17 | Primary source |
| Suspension of duty-free de minimis treatment — fact sheet | US Customs and Border Protection | 2025-08-29 | 2026-08-17 | Primary source |
| E-commerce: €150 customs duty exemption threshold to be removed in 2026 Confirms removal of the €150 duty exemption and a temporary interim calculation method until mid-2028. The Commission page does not itself state the flat per-parcel amount — see the Council release. | European Commission, DG TAXUD | 2026 | 2026-08-17 | Primary source |
| Selling on Amazon fee schedule Public page. Confirms referral fees of 5% to 45% by category, a $0.30 per-item minimum, the $1.80 media closing fee, and the $0.99 Individual versus $39.99 Professional plans. It does not publish the FBA size-tier rate card, which sits behind the Seller Central login. | Amazon | — | 2026-08-17 | Primary source |
| Update to European referral and Fulfilment by Amazon fees for 2026 Published by Amazon itself. The European fuel and logistics surcharge is 1.5%, not the 3.5% charged in the US and Canada — applying the US figure to a UK or German seller overstates their fulfilment cost by two points. | Amazon EU | 2026-04-17 | 2026-08-18 | Primary source |
| Zero referral fee on products under ₹1,000 From 16 March 2026 Amazon India charges no referral fee on roughly 12.5 crore products priced under ₹1,000, across more than 1,800 categories. A calculator that does not branch on the ₹1,000 line is materially wrong for the largest segment of Indian sellers. | Amazon India | 2026-03-16 | 2026-08-18 | Primary source |
| Update to US referral and Fulfilment by Amazon fees for 2026 Published by Amazon itself. Referral fees unchanged for 2026 — frozen since January 2024. Fulfilment fees up about $0.08 per unit on average from 15 January 2026. | Amazon | 2026-01-15 | 2026-08-18 | Primary source |
| Shopify plans and payment rates Plan prices and Shopify Payments rates vary by country and change on renewal. Confirm against the pricing page for your own region. | Shopify | — | 2026-08-17 | Primary source |
| Dimensional weight divisors by carrier FedEx and UPS daily rates use 139 for inches and pounds, 5000 for centimetres and kilograms. UPS retail counter rates use 166. DHL Express uses 5000. Compiled from carrier documentation and multiple independent operators; FedEx blocked our automated read on 2026-08-17. | ShipMargin (compiled) | — | 2026-08-17 | Corroborated |
| IATA volumetric ratio for air cargo (1:6000) 6000 cubic centimetres per kilogram, equivalently 167 kg per cubic metre. This is why an air-freight quote and a courier quote on the same box differ: couriers use 5000, giving 200 kg per cubic metre. | Air cargo standard practice | — | 2026-08-17 | Corroborated |
| LCL weight-or-measure (W/M) revenue tonne LCL is quoted per revenue tonne: whichever is greater of 1 cubic metre or 1,000 kg. | Ocean freight standard practice | — | 2026-08-17 | Corroborated |
| NMFC density-based classification, 2025 overhaul NMFTA replaced the legacy density tiers with a 13-tier scale and reclassified over 2,000 commodity codes. Density alone does not settle a class: stowability, handling and liability can all trigger a reclassification. | C.H. Robinson (reporting NMFTA Docket 2025-1) | 2025-07-19 | 2026-08-17 | Corroborated |
| Amazon FBA fee changes for 2026: three price bands From 2026-01-15 fulfilment fees split into three price bands — under $10, $10 to $50, and over $50 — instead of one fee per weight tier. Three independent sources agree. Most competing calculators still model a single fee per tier. | Goat Consulting | 2026-01-15 | 2026-08-17 | Corroborated |
| Amazon 3.5% fuel and logistics surcharge on FBA fees A 3.5% surcharge applied to the fulfilment fee itself, not the sale price, on FBA and Multi-Channel Fulfilment in the US and Canada from 2026-04-17 (2026-05-02 for MCF and Buy with Prime). Roughly $0.15 to $0.35 per unit on a standard item. | Fast FBA 3PL | 2026-04-17 | 2026-08-17 | Corroborated |
| eBay seller fees 2026 Standard final value fee 13.6% in most categories, plus a per-order fee of $0.30 on orders up to $10 and $0.40 above. The final value fee already includes payment processing under managed payments — adding a separate processing percentage double-counts, which at least one popular calculator appears to do. | Taxomate | 2026 | 2026-08-17 | Corroborated |
| Etsy fee structure and regulatory operating fees $0.20 listing fee, 6.5% transaction fee on the order total including shipping, plus country-specific payment processing and a regulatory operating fee in eight-plus countries. | Craftybase | 2026-03 | 2026-08-17 | Corroborated |
| De minimis suspension made indefinite by regulation Reports that CBP made the suspension indefinite by regulation from 2026-06-24, with statutory repeal following on 2027-07-01. Single source; confirm against the Federal Register before relying on the dates. | TariffsTool (reporting CBP rulemaking) | 2026-06-24 | 2026-08-17 | Secondary source |
| Council gives final green light to new customs duty rules for small parcels Secondary reporting describes a flat per-parcel duty of about €3 on consignments under €150 from 2026-07-01. Treat the exact amount as provisional until the Official Journal text is checked; our calculator exposes it as an editable field rather than a hidden constant. | Council of the European Union | 2026-07-01 | 2026-08-17 | Secondary source |
| How to calculate UK duty and VAT UK import VAT is charged on the customs value plus duty plus freight, at 20% standard or 5% reduced. Duty relief applies below £135 but VAT does not. | Customs Support | — | 2026-08-17 | Secondary source |
| De minimis values by country The most complete public table of per-country duty and tax thresholds we found, but it carries no publication date. Every threshold sourced from it is editable in the calculator and flagged in the results. | Zonos | — | 2026-08-17 | Secondary source |
| Amazon FBA fulfilment rate card 2026 Amazon's own rate card is login-gated, so every third-party figure — including ours — is a secondary reproduction. Directionally consistent across four independent sources. Verify against your own Seller Central rate card before pricing a product on it. | AMZ Prep | 2026-01-15 | 2026-08-17 | Secondary source |
| FBA storage fee revision, July 2026 Resolved on a third research pass: the 0.78-versus-0.87 disagreement was a genuine mid-year rate change rather than a source error. 0.78 was in force January to June 2026 and 0.87 took effect on 1 July, which is what we now apply. Also the origin for the aged-inventory ladder, which starts at 181 days. The 366-to-455-day band remains disputed between 0.79 and 6.90 per cubic foot, so we apply the lower figure and warn on it. | ConversionPerk / NovaData | 2026-07-01 | 2026-08-18 | Secondary source |
| Digital Services Fee — Amazon Europe A percentage uplift applied to Selling on Amazon fees and FBA fees, recovering national digital services taxes. Reported as rising to 3% and expanding to UK, France, Spain and Italy from 2026-03-20. The exact seller-country by marketplace-country matrix is the part we are least confident about, so the rate is an editable input. | Amazon Seller Central (FR help hub) | 2026-03-20 | 2026-08-17 | Secondary source |
| Amazon Currency Converter for Sellers rate tiers Volume-tiered from 1.50% under $100k of revenue down to 0.75% above $10M. Reports of an additional 2.5% to 4% markup over the mid-market rate are unverified, so the calculator asks for your own observed rate. | Titan Network | — | 2026-08-17 | Secondary source |
| VAT charged on Etsy seller fees UK sellers pay VAT on Etsy's fees themselves, so the effective fee burden is materially higher than the headline percentages. Only one competing calculator models this. | ListingPrep | 2026-06-22 | 2026-08-17 | Secondary source |
| TikTok Shop seller fees 2026 Reports a US referral fee of 6% covering both commission and payment processing, and 9% in the UK. This conflicts with a widely repeated 8% figure for the US. TikTok has stepped its US commission more than once, so the calculator defaults to 6% but makes the rate editable and shows both figures. | Dashboardly | 2026 | 2026-08-17 | Secondary source |
| Walmart Marketplace seller fees Referral fees of 6% to 15% by category with no monthly subscription. | Aura | — | 2026-08-17 | Secondary source |
What we know we do not know
A few things are genuinely unresolved, and it seems more useful to list them than to pretend otherwise.
- Amazon's exact FBA rate card. Amazon publishes it only behind the Seller Central login, so every third-party figure — ours included — is a secondary reproduction. Check your own fee preview before pricing a product.
- The EU's interim parcel duty amount. The Commission has confirmed the €150 exemption is going. Secondary reporting describes a small flat duty per parcel from July 2026. We have not read the Official Journal text, so we ask you to enter the amount rather than assuming it.
- TikTok Shop's US referral rate. Sources disagree between 6% and 8%, and TikTok has stepped the rate more than once. We default to 6%, say so on the page, and make it editable.
- The Digital Services Fee matrix. The existence and the 20 March 2026 date are well corroborated. Which rate applies to a seller established in country A selling on marketplace B is less clear.
- Nigeria's additional import levies. Single secondary source. Switched off by default and flagged in the results.
- The USPS divisor change. Five independent operators report the same change and the same PRC docket, but we have not read it off Postal Explorer directly, which is why it is marked corroborated rather than primary.
How to challenge a number
If a figure here disagrees with your invoice, your invoice is probably right and we want to know. Send the source you are working from and we will either update the registry or explain why the two figures differ — sometimes it is an account-specific rate, sometimes it is a genuine error on our side. Either answer is more useful than silence.