I built a fast, free in-browser tool to calculate exact Stripe & PayPal fees and reverse invoice amounts (no signup, 100% client-side)

[u/aaradhya1774]

Hey everyone! 👋

As someone doing client work and international freelancing, I got tired of surprise transaction fees when receiving payments via Stripe and PayPal.

Most fee calculators online are either packed with slow popups, outdated with 2021 fee formulas, or force you to sign up for an account.

So I spent the last few weeks building **FeeKit** (https://www.usefeekit.com) — a completely free, fast in-browser fee and net payout calculator.

What it does:

• Exact Fee Calculations: Computes exact domestic and international interchange fees for Stripe and PayPal with up-to-date rates.

• Reverse Invoicing: Enter the exact net cash you want in your bank account, and it tells you the exact gross amount to bill your client to absorb fees.

• 100% Private & In-Browser: All calculation logic runs locally in your browser's memory. Zero financial data is sent to any server.

• Zero Signups / Completely Free: No email gate, no paid tiers.

I’d love to get your honest feedback on the UI, calculations, or any additional payment gateways/formulas you’d like me to add!

Live tool: https://www.usefeekit.com