Billable Hours Calculator

Compute billable hours and an invoice subtotal for a single shift after subtracting any non-billable time. This is a single-session tool, distinct from the multi-entry Invoice Hours Calculator on this site.

Use it for freelance, contract, or consulting work where you charge by the hour for a single client session. It is also useful for verifying a single line item on a draft invoice before sending, or for translating a tracker export into a clean billable figure for your own records.

Billable minutes are end time minus start time minus break minutes. Billable hours are billable minutes divided by 60. The invoice subtotal is billable hours times your rate. Overnight sessions are handled with the standard 24 hour adjustment, so a session that starts at 10 PM and ends at 1 AM totals 3 hours.

The result shows total billable hours and the dollar value of the session in U.S. dollars. The hours figure is the line you would put on the invoice description; the dollar figure is the invoice subtotal before any tax or discount.

A 9:00 AM to 1:00 PM session with a 15 minute non-billable break is 3 hours 45 minutes billable, or 3.75 hours. At $75 an hour, that is $281.25. Bumping the rate to $125 (a senior consultant rate) takes the same session to $468.75. A 6 hour session with no break at $75 is $450.

The invoice value is pre-tax. If you collect sales tax, GST, or VAT, add that on top before sending the invoice. Some clients also expect line-item rounding (to the nearest 0.25 or 0.5 hour) on a draft, so confirm the rounding convention with the client before invoicing exact decimal hours. Track non-billable time separately so you can see your real utilization rate; consistently billing under 60 percent of your working hours is a sign your pricing or workload mix needs a second look. Review your billable mix every quarter and retire low-margin work that quietly drags your effective rate down without you noticing.