Estimates are wrong in one direction. The fix is not to guess harder but to name the uncertainty and the review rounds separately, so the client can see what they are paying for.
Project buffer calculator
Turn a raw estimate into a date you can commit to: add contingency for the unknown, review rounds, and the time the client will take to answer.
Hours to quote
128 h
Contingency
20 h
Review time
8 h
Uplift on the estimate
28%
Calculated instantly in your browser · no data sent
How it works
- 1Estimate the work itself, with no padding.
- 2Set the uncertainty from how firm the scope is.
- 3Count the review rounds the contract allows.
Who it's for
- •Quoting a fixed-price project
- •Planning a sprint
- •Explaining a price increase mid-project
Pro tips
- Ten to fifteen percent is a sensible floor when the scope is not locked.
- Write down how many rounds are included. Unlimited revisions is how a fixed price becomes an hourly one.
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