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Aradhya Pathak
Aradhya Pathak

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Why I Built FeeKit: A Fast, In-Browser Fee & Net Payout Calculator for Freelancers

#webdev #showdev #javascript #productivity

Every freelancer and digital agency owner knows the quiet frustration of payment day:

You send an invoice for $1,000, expecting a clean payout to your business account. But when the funds clear via Stripe or PayPal, you receive $962.40 (or worse, after international conversion and cross-border interchange cuts).

Surprise deductions chip away at hard-earned margins.

When I looked for calculators to solve this, I found three recurring problems:

  1. Outdated formulas: Most online calculators still use fee structures from 2021.
  2. Aggressive ad bloat: Popups, slow loading scripts, and layout shifts that take 5 seconds to load.
  3. Data harvesting: Demanding sign-ups, email capture, or storing transaction numbers on third-party databases.

So, I decided to build a fast, modern, and privacy-first solution: FeeKit.

🚀 What is FeeKit?

(https://www.usefeekit.com)** is a lightweight, zero-latency web utility designed for freelancers, indie hackers, and global contractors to compute payment processing deductions and reverse invoice amounts instantly.

Here is what it does right out of the box:

  • ⚡ Up-To-Date Fee Formulas:** Accurately calculates standard domestic and cross-border transaction fees for Stripe, PayPal, and major payment rails.
  • Reverse Billing (Net-to-Gross):** Ever wondered, "How much should I invoice my client so I walk away with exactly $2,500 in my pocket?" FeeKit calculates the gross invoice amount required to absorb processing fees completely.
  • 100% Client-Side Privacy:** Financial figures belong to you. All calculations run strictly inside your browser's local memory. Zero financial data is ever dispatched to an external server.
  • Zero Sign-Up Required:** No account creation, no password fatigue, and no paywalls. Just open the tool, calculate, and get back to building.

🛠️ The Tech Stack Behind FeeKit

I wanted FeeKit to feel as instantaneous as a native desktop utility:

  • Next.js 16 (App Router): Pre-rendered static pages deployed on edge CDN nodes for sub-100ms Time to First Byte (TTFB).
  • Pure Client-Side Math: Mathematical formulas execute in JavaScript memory without network roundtrips.
  • Clean Dark Mode UI: Engineered with an obsidian dark theme, zero layout shifts (CLS = 0), and keyboard-friendly responsive inputs.

💡 Try It & Share Your Feedback!

FeeKit is 100% free and live on the web:

👉 Live Platform: https://www.usefeekit.com

I'd love to hear your thoughts, feedback, and feature requests:

  • What other payment gateways or international currencies would you like to see?
  • Are there specific local tax formulas (VAT / GST) that would make your billing workflow smoother?

Drop your comments below! Happy invoicing! 💻✨

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