# Shop calculators

Free calculators for the owner of a repair shop. There is no account, no email to give and no pop-up.

## Parts markup matrix calculator

Works out what a part sells for under a parts matrix, and the margin the matrix makes across a shop's mix of parts.

- [Parts markup matrix calculator](https://open.wenmarpro.com/tools/parts-matrix)

## Labor rate calculator for auto repair shops

Works out the hourly labor rate a repair shop needs to cover its costs and leave a profit, and the rate it is getting for an hour billed.

- [Labor rate calculator for auto repair shops](https://open.wenmarpro.com/tools/labor-rate)

## Gross profit calculator for auto repair shops

Works out a repair shop's gross profit on labor, on parts, on sublet work and on all three together, and shows labor, parts and the overall figure beside a target.

- [Gross profit calculator for auto repair shops](https://open.wenmarpro.com/tools/gross-profit)

## Canadian invoice tax and tire fee calculator

Works out the GST, HST, PST or QST and the new-tire fees on a repair invoice in a Canadian province or territory, and the invoice's total.

- [Canadian invoice tax and tire fee calculator](https://open.wenmarpro.com/tools/canada-invoice-tax)

## Guides

Longer answers that go with the calculators.

- [How to build a parts matrix](https://open.wenmarpro.com/guides/parts-matrix)

## How they work

Each calculator is a form. What is typed goes into the page's address and nowhere else, so a result can be bookmarked, shared and printed, and nothing is stored.

Every calculator has a Markdown version at the same address with .md added. It states the formula and one worked example, and does not compute.