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Free Sample Size Calculator
Calculate required sample size for surveys and research studies.
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CalculateQuick Answer
For 95% confidence with 5% margin of error: need ~385 samples (large population). Larger samples = narrower margin of error.
Key Facts about Sample Size Calculator:
- 385 samples for 95% CI, 5% margin
- Larger sample = smaller margin
- Higher confidence needs more samples
- Population size matters less above 10K
- 95% confidence is standard
Why Use Our Sample Size Calculator?
Sample size tools:
📊
Survey Planning
Required sample size.
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Confidence Levels
90%, 95%, 99%.
🔢
Margin of Error
Set desired precision.
📐
Population
Finite population correction.
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Instant
Quick results.
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Data stays secure.
How to Sample Size Calculator in 3 Easy Steps
Calculate sample:
1
Set Parameters
Confidence and margin.
2
Enter Population
Population size.
3
Get Sample Size
Required n.
Why Use Our Calculator?
Research ready
Multiple confidence levels
Population correction
Instant results
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Sample Size
Plan your research
Frequently Asked Questions
Everything you need to know about our sample size calculator
How many responses do I need?
~385 for 95% confidence, 5% margin.
For 95% confidence, 5% margin with large population: ~385. See our calculator for exact needs.
Still have questions? Try the tool yourself!
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