Show HN: Stripe Fee Auditor – upload Balance CSV, see your real effective rate (not just 2.9%)

feeauditor.com

Most Stripe users pay 3.5–4% instead of the advertised 2.9%. Built this to show exactly why: international cards, Amex, refund fee retention, small transaction fixed costs.

No OAuth, no account needed. CSV processed in memory, not stored. Core logic on GitHub.