How this instrument works
Billable hours is the fraction of time worked that a client agrees to pay for, distinct from hours worked in general. A consultant, lawyer or freelance developer logs a full week at the desk, but proposals, internal meetings, admin, training and unpaid pitches all eat into that week without producing a line on any invoice. Utilization is the percentage that survives — the ratio of hours actually billed to hours actually worked — and it is the multiplier that turns a schedule into revenue.
The formula chains three figures rather than two: hours worked, the hourly bill rate, and utilization as a percentage. A straight hours-times-rate estimate assumes every hour in the week converts directly into paid work, which almost never happens once a practice grows past a single client. Utilization is the correction — it shrinks the naive total down to what a person or firm actually gets to charge for.
Reported utilization varies by field and by seniority: newer staff at agencies and law firms often sit lower while they learn the work, senior staff who also manage clients and pitch new business sit lower for a different reason, and the middle of a career in professional services tends to land somewhere between the two. This sheet takes utilization as a given input rather than computing it, so nothing here explains why a particular week ran low — only what that week is worth once the rate is applied.
- Enter Hours worked for the period you are sizing up — a week, a month, or a single project sprint.
- Set Hourly bill rate, $ to the rate a client is actually invoiced, not an internal cost figure.
- Set Utilization (% of hours actually billable) to the share of that time you expect to invoice; 100 assumes every hour is billable.
- Read Billable revenue for what those hours are worth once utilization has taken its cut.
Worked example — a 40-hour week at 75% utilization
Take a freelance developer who logs Hours worked as 40, sets Hourly bill rate, $ to 150, and estimates Utilization at 75 — a realistic figure once admin, unpaid proposals and internal meetings are subtracted from a working week. The instrument computes 40 times 0.75 times 150 and returns Billable revenue of $4,500.
A plain hours-times-rate estimate would promise $6,000 for that same week, and the missing $1,500 is not a rounding error — it is every hour spent chasing invoices, scoping unpaid work or fixing something nobody gets billed for. Raise utilization to 90% at the same rate and revenue climbs to $5,400 without a single extra hour worked; the lever here is time spent selling and administering, not time spent at the desk.
Questions
What counts as non-billable time?
Anything a client will not see a line item for: writing proposals, internal team meetings, training, marketing, chasing late invoices, fixing scope-creep work done for free, and unpaid time off. None of it disappears from the working week — it just does not appear in Billable revenue, which is exactly why utilization sits well below 100% for most people who both do the work and find the work.
How is this different from converting an hourly rate into a salary?
An hourly-to-salary conversion assumes every scheduled hour converts into pay, which suits a wage job where the employer absorbs downtime. This sheet is built for people who sell their own hours and are not paid for all of them, so it adds utilization as a third factor between hours and rate — a gap a salaried conversion has no reason to model.
What is a realistic utilization rate?
It varies by role and by how much of the job is winning and running the business versus doing the billable work itself. People early in a practice or focused mostly on client delivery often sit toward the higher end; those who also manage staff, pitch new clients or run the back office sit lower. There is no single correct number — set it from your own recent invoicing, not a rule of thumb.
Does Billable revenue equal what actually gets paid?
No. It is the invoiced value of the hours entered, before any client disputes a line item, pays late, negotiates a discount, or before tax and business expenses come out the other side. Treat it as the top of the funnel — what the work is worth at the rate quoted — not the cash that eventually clears your account.
How do I find my own utilization percentage instead of guessing?
Divide the hours you actually invoiced in a period by the hours you worked in that same period, then multiply by 100. Someone who worked 40 hours and billed 30 of them is running 75% utilization. Doing this over a few real weeks, rather than a single busy or slow one, gives a figure worth trusting in this calculator.
References
- U.S. Small Business Administration — Manage your finances
- IRS — Self-employment tax (Social Security and Medicare)
- Bureau of Labor Statistics — Occupational Employment and Wage Statistics
Read this first: This instrument shows arithmetic, not advice. Real offers add fees, taxes and terms that vary by lender and place — verify the figures against your actual paperwork before deciding anything.