Statistics & Probability
Confidence Interval Calculator
Lets users solve and check confidence interval instantly with formula, steps and examples — no manual math.
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Your result
Lower bound
94.6323
CI: 100 ± 5.368 = [94.632, 105.368].
Upper bound
105.3677
Margin of error
5.3677
Standard error
2.7386
About this calculator
Confidence interval for a mean: x̄ ± z·(σ/√n). The margin of error grows with confidence level and shrinks with larger samples. 95% uses z = 1.96.
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