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Project Cost Estimator
Clients often want a fixed price instead of an hourly rate. Estimate a fair flat price by multiplying your estimated hours by your hourly rate, then adding a buffer for scope creep, revisions and communication overhead.
recommended 20–30%
Suggested flat price
$11,250
120h × $75 + 25% buffer = $11,250
Why add a buffer?
Fixed-price projects almost always overrun the estimate: clients request revisions, meetings multiply, and "quick" changes add up. A 20–30% buffer is the difference between a project that pays your rate and one that quietly pays below it.
The formula
flat price = hours × hourly rate × (1 + buffer/100)
Pricing checklist
- Write down every deliverable the price covers.
- State the number of revision rounds included.
- Define what counts as out of scope — and its hourly rate.
- Never charge a buffer that isn't in the written proposal.