{{-- Header --}}
{{-- Body --}}
{{-- Section 2: Two cards side by side --}}
i
Sample Size Formula
Base Formula
n0 = (Z² × p × (1 − p)) / e²
Standard Cochran formula for large populations where sample proportion is known or estimated.
With Finite Correction
n = n0 / (1 + (n0 − 1) / N)
Used when the population is small and the sample size represents a significant portion of N.
{{-- LEFT: Calculation Parameters --}}
 }})
Calculation Parameters
{{-- Confidence Level --}}
{{-- Resolved Z-score badge from /api/confidence-score --}}
{{-- Estimated Proportion --}}
{{-- Margin of Error --}}
{{-- Population Size --}}
{{-- Calculate button with loading state --}}
{{-- API Error banner --}}
{{-- RIGHT: Result --}}
Calculation Parameters
Confidence Level
Enter as decimal — 90% = 0.90, 95% = 0.95
@foreach(['90%' => 0.90, '95%' => 0.95, '99%' => 0.99] as $label => $val)
@endforeach
Resolved Z-score:
Estimated Proportion (p)
Use 0.5 for most conservative estimate
@foreach(['10%' => 0.1, '30%' => 0.3, '50%' => 0.5] as $label => $val)
@endforeach
Margin of Error (e)
Enter as decimal — 5% = 0.05
@foreach(['1%' => 0.01, '5%' => 0.05, '10%' => 0.1] as $label => $val)
@endforeach
Population Size (N)
Optional
Required Sample Size
-
units
Based on selected parameters
Result Summary
Confidence Interval
± 5.0%
Confidence Level
95%
Proportion (p)
0.50
n₀ (base sample)
-
n (finite corrected)