About PenguinCalc
PenguinCalc is an independent calculator directory for online sellers, freelancers, and small businesses that need clear fee and profit estimates before they price a product, send an invoice, or compare payment options.
Why We Build These Calculators
Payment and commerce platforms often publish rates across several pages, with different add-ons for transaction type, country, currency, payment method, plan level, and custom pricing. PenguinCalc turns the common public assumptions into practical calculators so users can see the result, formula, and limitation in one place.
Our goal is not to replace official dashboards or professional advice. The goal is to help users estimate the business decision in front of them: how much they keep, what to charge, which fee matters most, and when the estimate may differ from the final provider statement.
Source Review
For fee-based calculators, we start from official pricing or fee pages whenever possible. When a calculator uses simplified defaults, the page states the assumption and links users back to the relevant provider documentation.
Formula Checks
We separate fixed fees, percentage fees, optional add-ons, and reverse calculations. Key examples are checked against known amounts so users can spot whether the calculator is behaving as expected.
Update Notes
Calculator pages include a last reviewed or last checked note when fee data matters. If rates change, the calculator and the surrounding explanation should be updated together.
Corrections
If a user finds a rate that appears outdated, we ask for the page URL, selected settings, test amount, observed result, and source being compared. This keeps corrections specific and verifiable.
What Our Calculators Include
Most calculators include a working tool, common defaults, examples, source or assumption notes, a disclaimer, and FAQ content written around practical user questions. We avoid publishing placeholder tools on the homepage because unfinished pages are not helpful to users.
Independence and Limitations
PenguinCalc is independent and is not affiliated with, endorsed by, or sponsored by PayPal, Stripe, Shopify, or any other platform mentioned on the site. Trademarks belong to their respective owners and are used only for identification and comparison.
Calculator results are estimates for educational use. Actual fees can vary by country, account type, currency, payment method, plan, tax treatment, negotiated pricing, refunds, disputes, and platform policy changes.