Professional-services utilization tool
Billable Hours Calculator
Calculate billable utilization, non-billable time, target hours, the gap to target and revenue for one comparable period.
Utilization and revenue results
Billable hours and utilization formulas
Billable utilization = billable hours ÷ available hours × 100.
Non-billable hours = available hours − billable hoursTarget billable hours = available hours × target utilization ÷ 100Gap or surplus = billable hours − target billable hoursBillable revenue = billable hours × billing rateRevenue per available hour = billable revenue ÷ available hoursAnnualized revenue = period revenue × comparable periods per year
A positive gap is a surplus above the target; a negative gap is the additional billable time needed to reach it.
Checked examples
| Inputs | Calculation | Result |
|---|---|---|
| 160 available hours, 120 billable, 75% target, $150/hour | 120 ÷ 160; 120 × $150 | 75% utilization, 40 non-billable hours, $18,000 revenue and a 0-hour gap |
| 160 available hours, 104 billable, 75% target, $200/hour | 104 ÷ 160; target = 160 × 75% | 65% utilization, 16 hours below target and $20,800 revenue |
| 40 available hours, 34 billable, 80% target, €125/hour | 34 ÷ 40; target = 32 hours | 85% utilization, 2 hours above target and €4,250 revenue |
What counts as available and billable time?
Available hours are the workable hours included in your chosen period after applying your organization’s capacity convention. Billable hours are the hours chargeable to a client under the engagement’s billing rules. Use the same person, team and period for both inputs.
Internal meetings, training, administration, business development, leave and holidays may be treated differently by each organization. Decide the policy first, then enter consistent totals. This calculator does not classify individual time entries.
Billing increments and decimal hours
Some firms record time in fixed increments. Divide minutes by 60 before entering hours. Always follow the engagement terms and applicable professional rules rather than automatically rounding every entry upward.
| Minutes | Exact decimal hours | Common 0.1-hour increment | Common 0.25-hour increment |
|---|---|---|---|
| 6 | 0.10 | 0.1 | 0.25 if the policy permits rounding |
| 12 | 0.20 | 0.2 | 0.25 |
| 15 | 0.25 | 0.3 if rounding up by 0.1 | 0.25 |
| 30 | 0.50 | 0.5 | 0.50 |
| 45 | 0.75 | 0.8 if rounding up by 0.1 | 0.75 |
| 60 | 1.00 | 1.0 | 1.00 |
Limits and assumptions
- Available hours must be greater than 0 and no more than 1,000,000 per period.
- Billable hours can be 0 through 1,000,000 and cannot exceed available hours in this utilization model.
- Target utilization must be greater than 0% through 100%; billing rate must be greater than 0 through 1,000,000.
- Comparable periods per year must be a whole number from 1 through 366; use it only when periods are genuinely comparable.
- Revenue is gross billed value before discounts, write-offs, collection losses, taxes, payroll, overhead and profit. Total displayed revenue is capped at 1 billion.
- Currency changes formatting only. No exchange rates are applied.
Important: utilization targets are management inputs, not universal standards. This tool does not determine ethical billing, compliance, staffing capacity, profitability or compensation. Do not treat annualized revenue as a forecast unless future workload, rates and collection remain comparable.
Frequently asked questions
Can billable utilization exceed 100%?
Some businesses define capacity so that reported billable hours can exceed a nominal schedule. This calculator intentionally limits billable hours to available hours because it uses a 0%–100% utilization model. If your organization uses a different denominator, calculate that denominator first and apply its own policy.
Is revenue the same as collected cash?
No. The estimate multiplies billable hours by the entered rate. Discounts, write-downs, unbilled work, bad debt and payment timing can make collected cash different.
Should leave and holidays reduce available hours?
That depends on the utilization policy. Some organizations exclude leave and holidays from capacity; others use a fixed standard. Use the denominator required by the metric you are reporting.
Related calculators
- Time Card Calculator — total clock-in, clock-out and break entries before classifying billable time.
- Employee Cost Calculator — estimate fully loaded labor cost and cost per productive hour.
- Salary Calculator — convert gross pay between hourly and annual periods.
- Overtime Calculator — calculate gross pay from regular, overtime and double-time hours.