About Seller Fees Calculator
Seller Fees Calculator is a local MCP server for US sellers using Gumroad, Stripe, PayPal, or Etsy. It calculates fees, net payouts, and prices needed to reach a target after fees, without API keys or network calls.
Key features
- 01Calculate fees and net per sale
- 02Estimate payouts across multiple units
- 03Find price needed for a target net
- 04Compare net proceeds across platforms
- 05View default rates and options
Use cases
- 01Estimate earnings from a planned sale
- 02Set a price to meet a net-income target
- 03Compare fees across supported platforms
MCP support
It exposes fee, payout, target-price, comparison, and platform-information tools to MCP clients. Calculations run locally without API keys or network calls.
Configuration
Local server config is the same for every client. Copy it into your client’s MCP config file.
Tools
5Saved tool list · updated 3d ago
| Parameter | Type | Required | Description |
|---|---|---|---|
| qty | integer | No | Etsy: items in the order |
| type | enum | No | PayPal payment type (default checkout)checkout | venmo | card | goods | paylater | other |
| amount | number | Yes | Sale price in USD (Etsy: item price) |
| discover | boolean | No | Gumroad: sale came through Gumroad Discover (flat 30%, processing included) |
| platform | enum | Yes | gumroad | stripe | paypal | etsy |
| shipping | number | No | Etsy: shipping charged to the buyer |
| extra_pct | number | No | Stripe: extra % for international cards or currency conversion |
| gift_wrap | number | No | Etsy: gift wrap charged |
| processing | enum | No | Gumroad direct: add card processing 2.9% + $0.30 (default card)card | none |
| high_volume | boolean | No | Gumroad: 5% + $0.50 tier (paid sales this calendar month reached $20,000) |
| offsite_ads | enum | No | Etsy: Offsite Ads fee (std 15%, low 12%)none | std | low |
| international | boolean | No | PayPal: international buyer (+1.50%) |
| sales_tax_pct | number | No | Etsy: sales tax % on the order |
Details
From the project READMEseller-fees-mcp
A free Model Context Protocol (MCP) server that works out seller fees, payouts and break-even prices for Gumroad, Stripe, PayPal and Etsy (US sellers, USD). Everything runs locally: no API key, no account, no network calls.
Tools
| Tool | What it does |
|---|---|
fee | Fee and net for one sale. Gumroad direct includes the 2.9% + $0.30 card processing; options discover, high_volume, processing (card/none). PayPal type and international, Stripe extra_pct, Etsy qty, shipping, sales_tax_pct, offsite_ads. |
payout | What you keep per sale and in total for units sales. |
price_for_target | Lowest price that leaves at least target after fees. |
compare | One price across Gumroad direct, Gumroad Discover, Stripe, PayPal (checkout, card, goods) and Etsy, best net first. |
platforms | Default rates, options and official source pages. |
Default rates are as of Oct 20, 2026. Gumroad direct: 10% + $0.50 plus card processing 2.9% + $0.30 (5% + $0.50 with high_volume); Discover: 30% all-in. Stripe: 2.9% + $0.30. PayPal Checkout: 3.49% + $0.49. Etsy: $0.20 listing, 6.5% transaction, 3% + $0.25 processing. Check each platform's pricing page before relying on a number. Planning estimates only; not tax or accounting advice.
Install
Requires Node.js 18 or newer.
npx
npx -y seller-fees-mcp
From source
git clone https://github.com/NarwhalThePong/seller-fees-mcp.git && cd seller-fees-mcp && npm install && npm test
node src/server.js
Desktop MCP clients
Add to your client's MCP config file:
{
"mcpServers": {
"seller-fees": { "command": "npx", "args": ["-y", "seller-fees-mcp"] }
}
}
Cursor
Add to ~/.cursor/mcp.json (or .cursor/mcp.json in a project):
{
"mcpServers": {
"seller-fees": { "command": "npx", "args": ["-y", "seller-fees-mcp"] }
}
}
For a local checkout, use "command": "node", "args": ["/path/to/seller-fees-mcp/src/server.js"].
Example
fee with { "platform": "gumroad", "amount": 19 } returns a fee of $3.25 ($2.40 Gumroad + $0.85 card processing) and a net of $15.75.
Prefer a web page?
- Free Gumroad fee calculator: https://narwhalthepong.github.io/gumroad-license-check/gumroad-fee-calculator.html
- Free PayPal and Stripe fee calculator: https://narwhalthepong.github.io/gumroad-license-check/paypal-stripe-fee-calculator.html
- Free Etsy fee calculator: https://narwhalthepong.github.io/gumroad-license-check/etsy-fee-calculator.html
- Creator Payout Calculator Pro (browser extension, paid): https://paudrudis.gumroad.com/l/ijrzbz
Disclosure: these are our own products. The calculator pages are free; Creator Payout Calculator Pro is a paid product we sell.
License
MIT
Comments
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