Confidence Interval Calculator
Large-n educational CI using z critical; notes sample vs known population SD.
Limitation: Educational inferential statistics.
How to Use the Confidence Interval Calculator
Large-n educational CI using z critical; notes sample vs known population SD.
Open the CI calculator and read field labels.
Match the mode
Educational inferential statistics.
What It Calculates
Large-n educational CI using z critical; notes sample vs known population SD.
Worked Examples
95% CI
Inputs
Result
ME ≈ 1.48.
99% wider
Inputs
Result
Higher z*.
Small n note
Inputs
Result
Consider t for tiny samples.
Check your mode
Educational inferential statistics.
Frequently Asked Questions
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Standard definitions with assumptions noted below.
Formula
Scientific Background
Standard statistics definitions with assumptions stated on-page. Educational only—not professional certification.
Sources & review
Confidence Interval Calculator documents the references behind its formulas and assumptions. Always treat results as educational estimates, not personalized professional advice.
Last reviewed
July 22, 2026
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