Rex says
Money math without the spreadsheet headache. Plug in your numbers and I'll show you exactly where the dollars land.
Try a scenario
Click to load — tweak from there.Inputs
Result
Break-even hours (hourly = flat)
12.9
Hourly cost at estimate
$4,200
Hourly cost if case runs over
$5,670
Cheaper option at estimate
Hourly is cheaper
Cheaper option if overrun
Flat fee protects you here
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How to use this
- 1Enter attorney hourly rate ($/hr).
- 2Enter estimated hours needed.
- 3Enter competing flat fee quote ($).
- 4Enter pessimistic time overrun (%).
- 5Read your break-even hours (hourly = flat) on the right — it updates as you type.
- 6Hit Share to keep the scenario or send it to someone.
About this calculator
Hourly billing charges for actual time spent and gives you a bill that fluctuates with case complexity, while flat fees fix the price regardless of how many hours the matter takes. Hourly makes sense when a case is simple and predictable, since you only pay for time actually used. Flat fees protect you when a case might balloon in scope, like a contested divorce or a litigated business dispute, because the attorney absorbs the risk of extra hours. This calculator takes your estimated hours, hourly rate, and a competing flat fee quote, and tells you the break-even hour count where both options cost the same, plus which option wins at your estimated hour count and at a pessimistic higher estimate, since legal matters routinely run 20-50% over initial time estimates.
Worked example
Using the values the calculator loads with:
Inputs
- Attorney hourly rate: 350 $/hr
- Estimated hours needed: 12
- Competing flat fee quote: 4500 $
- Pessimistic time overrun: 35 %
Results
- Break-even hours (hourly = flat): 12.9
- Hourly cost at estimate: $4,200
- Hourly cost if case runs over: $5,670
- Cheaper option at estimate: Hourly is cheaper
- Cheaper option if overrun: Flat fee protects you here
What each field means
Inputs
- Attorney hourly rate ($/hr)
- The attorney hourly rate used in the calculation, measured in $/hr. Starts at 350 $/hr so you have a working example on load.
- Estimated hours needed
- The estimated hours needed used in the calculation. Starts at 12 so you have a working example on load.
- Competing flat fee quote ($)
- The competing flat fee quote used in the calculation, measured in $. Starts at 4500 $ so you have a working example on load.
- Pessimistic time overrun (%)
- The pessimistic time overrun used in the calculation, measured in %. Starts at 35 % so you have a working example on load. Accepted range: 0–200 %.
Results
- Break-even hours (hourly = flat)
- Returned as a decimal number and shown as the headline result. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Hourly cost at estimate
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Hourly cost if case runs over
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Cheaper option at estimate
- Returned as a plain value. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Cheaper option if overrun
- Returned as a plain value. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
FAQ
When should I push for a flat fee?
Whenever the scope of work is inherently unpredictable, like a contested custody case, a litigated business dispute, or any matter where the other side could add complexity through delay or aggressive tactics. Flat fees shift that unpredictability risk onto the attorney.
Why would an attorney prefer hourly billing?
Hourly billing removes their risk of underestimating a matter's complexity, and it's the default for litigation where outcomes and opposing counsel's behavior are outside their control. Attorneys typically only offer flat fees for well-defined, repeatable work like an uncontested divorce, a standard will, or an LLC formation.
Does a flat fee cover everything?
Read the engagement letter carefully. Many flat fees exclude court costs, filing fees, expert witnesses, and appeals, and some cap the flat fee to a defined scope, charging hourly for anything beyond it, like a case that goes to trial after a flat-fee negotiation attempt.
Is a retainer the same as a flat fee?
No. A retainer is typically a deposit against future hourly billing, refundable if unused, while a flat fee is the full agreed price for defined work regardless of hours actually spent, and generally non-refundable once work begins.
Accuracy and limitations
- Results are estimates before tax, fees, and inflation unless an input explicitly covers them.
- Rates are treated as fixed for the whole period — variable-rate products will drift from this projection.
- This is educational maths, not financial advice. Check anything contractual with the lender or your accountant.
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Cite this calculator
Writing about this topic? Grab a citation — every link helps keep these tools free.
RevenueLab. (2026). Attorney Hourly vs Flat Fee Calculator. Retrieved from https://www.revenuelab.fyi/toolbox/attorney-hourly-vs-flat-fee
<p>Source: <a href="https://www.revenuelab.fyi/toolbox/attorney-hourly-vs-flat-fee" target="_blank" rel="noopener">Attorney Hourly vs Flat Fee Calculator — RevenueLab</a> (2026).</p>
Source: [Attorney Hourly vs Flat Fee Calculator — RevenueLab](https://www.revenuelab.fyi/toolbox/attorney-hourly-vs-flat-fee) (2026).