Guesstimate
Definition 1 of 1

Context
Use 'guesstimate' when precision is not required.

It is suitable for informal communication.
Formality
Avoid using 'guesstimate' in formal reports.

Use 'estimate' in business documents.
Nuance
A 'guesstimate' implies uncertainty.

It suggests that the speaker is not confident in the exact number.
Compare with
estimatorguessprojectionassumptioncalculate
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