calc.engineer / General & Math / Sales Tax

Sales Tax v1.0.0

Calculates total cost including sales tax for a purchase. Given a unit price, tax rate percentage, and optional quantity, computes the subtotal (price times quantity), the tax amount rounded to two decimal places, and the final total. Useful for estimating purchase costs across US states and municipalities with different tax rates, comparing pre-tax and post-tax prices, and budgeting. Chain into salary_to_hourly to see how many work-hours a purchase represents.

feeds salary_to_hourly →
Unit price of the item in dollars (or any currency). Must be positive.
Sales tax rate as a percentage (e.g. 8.875 for 8.875%). Defaults to 0 — enter your local rate.
Number of items to purchase. Defaults to 1.
Fill in the inputs and Compute to see the structured result.

From an agent (MCP) or the API

curl -X POST https://calc.engineer/api/sales_tax \
  -H "Content-Type: application/json" \
  -d '{"price": …, "tax_rate_pct": …, "quantity": …}'

MCP: connect to https://calc.engineer/mcp and call sales_tax.

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