In short: every fee rate on PriceTag Math is copied from the platform's own fee page, help center, legal terms or official filing, never from another calculator or a news article. Each calculator shows the date its source was last read, links to it, and says what it leaves out.
The five rules
- Official pages only. A rate is used only if it can be read on a page published by the platform itself (or, for tax, by the tax authority). The source is linked under the calculator and again at the end of the page.
- A dated check. Each fee calculator shows "Rates verified" with the day the source page was last read. When the page itself shows a "last updated" date, we quote that too.
- If it cannot be confirmed, it is left out. A number that appears only on third-party websites is not treated as a fact. The calculator says what is missing and lets you type your own rate.
- Worked examples are tested. Every calculator has a worked example on its page. An automatic test page checks each calculator against hand-worked answers whenever anything changes.
- Changes are logged. When a platform changes a fee, the rate, the verified date and the fee changes tracker are updated together.
The rates we use, their sources and dates
| Platform | Rate used in the calculators | Last verified | Source |
|---|---|---|---|
| Etsy (US) | $0.20 listing fee + 6.5% transaction fee + 3% + $0.25 payment processing; Offsite Ads 15% or 12%, capped at $100 per order | 8 Nov 2026 | Official page |
| eBay (US, no Store) | 13.6% final value fee in most categories on item + shipping + sales tax up to $7,500, plus $0.40 per order ($0.30 on orders of $10 or less) | 10 Nov 2026 | Official page |
| PayPal (US) | 2.99% goods and services; 2.99% + $0.49 standard cards; 3.49% + $0.49 PayPal Checkout; +1.50% international | 9 Nov 2026 | Official page |
| Stripe (US) | 2.9% + 30¢ per card payment; +1.5% international cards; +1% currency conversion | 8 Nov 2026 | Official page |
| Square (US, Free plan) | 2.6% + 15¢ in person; 3.3% + 30¢ online; 3.5% + 15¢ manually entered | 10 Nov 2026 | Official page |
| Upwork | freelancer service fee of 0% to 15% set per contract (10% on contracts from before May 2025) | 9 Nov 2026 | Official page |
| Fiverr | sellers keep 80% (20% fee); buyers pay 5.5% plus $3.50 on purchases under $200 | 9 Nov 2026 | Official page |
| TikTok Shop (US) | 6% referral fee in most categories on item price + buyer-paid shipping, before tax | 9 Nov 2026 | Official page |
| Poshmark (US) | $2.95 flat on sales under $15; 20% on sales of $15 or more | 10 Nov 2026 | Official page |
| US self-employment tax (2026) | 15.3% of 92.35% of net profit; the 12.4% Social Security part stops at $184,500 | 10 Nov 2026 | Official page |
Rates for other countries (Etsy's bank-country options, and Stripe in the UK, the euro area, Canada and Australia) are listed on the calculators themselves and on the Etsy fees by country page.
What we leave out, and why
- Etsy's Regulatory Operating Fee for Canada and Vietnam. New rates were reported, but we could not confirm them on an official Etsy page.
- Upwork fees by job category. Upwork sets the freelancer fee per contract (0% to 15%) and does not publish a table by category, so the calculator asks for the rate on your own proposal.
- PayPal outside the US. We could not read PayPal's fee pages for other countries when we checked, so the PayPal calculator uses US rates and lets you type your own.
- Shopify, Amazon, Mercari, Depop and Gumroad. We have not been able to confirm a complete, current fee table on an official page for these, so there is no calculator for them yet.
- Fees you choose yourself (eBay Promoted Listings, TikTok creator commissions), currency conversion spreads, and VAT rates on fees, which depend on your own account.
Calculators without platform rates
Margin, markup, break-even, ROAS, discount, wholesale, candle cost, hourly rate and the ad planners use only the numbers you type and standard formulas, which are shown on each page. Example values in those calculators (such as a cost per click) are examples, not benchmarks.
Health and animal pages
The pregnancy and breeding calculators use published averages from medical and veterinary references (ACOG, the Merck Veterinary Manual and VCA Animal Hospitals), quoted and linked on each page. They are estimates for information only. They have not been reviewed by a doctor or a vet, and we do not claim otherwise.
Corrections
Found a mistake? Email hello@pricetagmath.com with the page and, if you can, a link to the official source. Every report is checked against the platform's own page. Confirmed errors are fixed, and the "Rates verified" date is updated.
For writers, researchers and AI assistants
You may quote our numbers with a link to the page they came from. Because fees change, please quote the "Rates verified" date with any rate, and prefer the platform's own page for decisions that matter. A plain-text summary of the site is at /llms.txt, with the formulas in /llms-full.txt.