Hong Life CalculatorsUnderstanding the fixed-fee project hours — concept and principle
When a client offers a fixed price for a project instead of paying by the hour, the real question is what that price is worth per hour of your time. This calculator converts a fixed fee into an effective hourly rate based on your own time estimate, shows how many hours the fee covers at your target rate, and tells you what fee your estimate would justify. Freelancers, agencies and consultants use it before accepting or quoting a fixed-price job. It works with any currency.
How it is calculated
- Effective hourly rate = fixed fee ÷ estimated hours
- Hours the fee covers = fixed fee ÷ target hourly rate
- Fee needed for your estimate = estimated hours × target hourly rate
The fixed fee is the total price offered, the target hourly rate is what you normally aim to earn, and estimated hours is your honest forecast of the time the work will take, including meetings, revisions and admin.
The principle
A fixed fee moves the risk of overruns from the client to you. If the job takes longer, your income stays the same and your hourly rate falls. The three outputs look at the same deal from three angles: what you earn per hour if your estimate is right, how much time you can spend before dropping below your target, and what price would match your target exactly. The gap between hours covered and hours estimated is your buffer against scope creep.
Worked example
- Effective rate = 6,000 ÷ 70 = $85.71 an hour, above the $75 target.
- Hours covered = 6,000 ÷ 75 = 80 hours.
- Fee needed = 70 × 75 = $5,250.00.
- The offer is $750 above what you need, which gives a buffer of 10 hours, or about 14% more time than estimated, before you fall below $75 an hour.
How to read the result
If the effective rate is above your target, the deal is acceptable as long as your estimate holds. If it is below, renegotiate the price, reduce the scope, or decline. Projects often take longer than first planned, so a buffer of 10–25% is a sensible margin of safety, larger for unfamiliar work or vague briefs.
Common mistakes
- Estimating only production time and forgetting calls, emails, feedback rounds and invoicing.
- Ignoring out-of-pocket costs such as stock images, travel or subcontractors.
- Accepting unlimited revisions in a fixed-price contract.
- Not writing down the agreed scope, which makes extra work hard to bill.
FAQ
Frequently asked questions
Is fixed pricing better than hourly billing?
It can be if you work efficiently and the scope is clear, because faster delivery raises your effective rate. With unclear scope, hourly or milestone billing protects you better.
How can I improve my time estimate?
Track the hours spent on past projects and compare them with what you estimated. Many people find they consistently underestimate by a similar ratio.
Should I tell the client my hourly rate?
Not necessarily. With fixed pricing the client compares outcomes and total price, so you can price on value rather than time.
Sources: Project Management Institute — A Guide to the Project Management Body of Knowledge (PMBOK Guide)