Job Costing Calculator

What job costing is (and why estimates are not enough)

Job costing means tracking the actual costs of each job against the price you charged for it. Your estimate is a prediction; job costing is the scorecard. Without it, you only find out whether a job made money when the year-end numbers come in - long after you have quoted ten more jobs the same way.

The five cost categories to track

1. Materials - everything bought for the job, including returns you never processed and extra trips to the supplier.
2. Labor - hours times the fully loaded rate (wages, payroll taxes, workers comp, benefits).
3. Subcontractors - every sub invoice tied to the job.
4. Equipment and rentals - rentals, fuel, small tools consumed, dump fees.
5. Overhead allocation - the job’s share of insurance, vehicles, office and admin time.

How to job-cost a finished job in five minutes

1. Pull the final invoice total (including approved change orders) - that is your revenue.
2. Total the supplier receipts and card charges for the job.
3. Multiply crew hours by your loaded labor rate.
4. Add sub invoices, rentals and permits.
5. Add overhead: a simple method is your annual overhead divided by annual revenue, applied as a percentage of this job’s price.
6. Enter the numbers above and read the margin.

Estimated vs. actual: where margin usually leaks

• Labor running long on the parts of the job you estimate least often.
• Change orders done in the field and never billed.
• Material prices that moved between the quote and the purchase.
• Callbacks and punch-list trips after final payment.

Compare each category against your estimate. The category with the biggest gap is where your next estimate needs a correction.