Write a tool-page introduction that answers the first question

Help readers decide whether a calculator fits before entering numbers.
Name the input and the decision
A promotion calculator should say that it estimates orders needed to match normal contribution. Name the kind of margin it uses before a reader enters revenue by mistake.

Give the fastest valid path
Put a usable example near the form and explain unusual fields beside the labels. Move longer interpretation below the result. A returning reader should not have to scroll through background material each time.
Test the opening without the title
Ask someone to explain what the tool will calculate after reading just the first paragraph. If their answer describes a different metric, revise the promise and field wording together.
Try a related tool
Find the share of eligible visits that completed a defined action. Count at most one conversion per visit for this calculation.


