Marketplace Fee Calculator

Work out seller fees on Amazon, eBay, Etsy and Shopify. Returns total fees, net revenue and the breakdown.

Pay by wallet (x402) marketplace-fee-calculate

Example

Input

{
  "category": "electronics",
  "sale_price": 100,
  "marketplace": "amazon"
}

Answer

{
  "fees": {
    "other_fees": null,
    "closing_fee": null,
    "listing_fee": null,
    "referral_fee": 8,
    "transaction_fee": null,
    "payment_processing_fee": null
  },
  "category": "electronics",
  "currency": "USD",
  "sale_price": 100,
  "total_fees": 8,
  "fee_percent": 8,
  "marketplace": "amazon",
  "net_revenue": 92,
  "breakdown_notes": [
    "Referral fee: 8.0% of sale price",
    "Professional seller plan ($39.99/month not included in per-item calculation)",
    "FBA fulfillment fees not included (varies by size/weight)"
  ]
}

Inputs

Field	Type	Required	What it is
`category`	string	No	—
`sale_price`	number	Yes	—
`marketplace`	string	Yes	amazon/ebay/etsy/shopify

Output fields

How reliably each field appears in a successful answer.

Field	Type	Appears
`fees`	object	Always (present in every successful answer)
`total_fees`	number	Always (present in every successful answer)
`fee_percent`	number	Always (present in every successful answer)
`net_revenue`	number	Always (present in every successful answer)

How to call it

The same tool through each route. MCP clients reach it through Strale’s server at https://api.strale.io/mcp; the call below is what the agent sends.

# Needs an API key. max_price_cents caps what this call may cost.
curl -X POST https://api.strale.io/v1/do \
  -H "Authorization: Bearer $STRALE_API_KEY" \
  -H 'Content-Type: application/json' \
  -d '{
    "capability_slug": "marketplace-fee-calculate",
    "inputs": {
      "category": "electronics",
      "sale_price": 100,
      "marketplace": "amazon"
    },
    "max_price_cents": 5
  }'

{
  "tool": "strale_execute",
  "arguments": {
    "slug": "marketplace-fee-calculate",
    "inputs": {
      "category": "electronics",
      "sale_price": 100,
      "marketplace": "amazon"
    },
    "max_price_cents": 5
  }
}

import { Strale } from "straleio";

const strale = new Strale({ apiKey: process.env.STRALE_API_KEY! });
const result = await strale.do({
  capability_slug: "marketplace-fee-calculate",
  inputs: {
    "category": "electronics",
    "sale_price": 100,
    "marketplace": "amazon"
  },
  max_price_cents: 5,
});

import os
from straleio import Strale, DoRequest

strale = Strale(api_key=os.environ["STRALE_API_KEY"])
result = strale.do(DoRequest(
    capability_slug="marketplace-fee-calculate",
    inputs={
        "category": "electronics",
        "sale_price": 100,
        "marketplace": "amazon",
    },
    max_price_cents=5,
))

# No account. The first request answers 402 with the price in USDC;
# an x402 client pays it from your wallet and repeats the request.
curl -i 'https://api.strale.io/x402/v2/marketplace-fee-calculate?category=electronics&sale_price=100&marketplace=amazon'

Limitations

Actual fees vary by category and seller tier
Fee structures based on AI knowledge — marketplaces update fees periodically and actual fees depend on seller tier and category
What to do instead: Verify calculated fees against the marketplace's current seller fee schedule before pricing decisions

Related tools

Meeting Time Finder €0.03
Payment Reference Generator €0.02