Sample Size Calculator Surveymonkey

SurveyMonkey Sample Size Formula:

\[ \text{Sample Size} = \frac{\text{Population}}{1 + \text{Population} \times \frac{\text{Margin of Error}^2}{\text{Confidence Level}^2}} \]

Population Size:

people

Margin of Error:

Confidence Level:

Recommended Sample Size:

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1. What is the SurveyMonkey Sample Size Formula?

The SurveyMonkey sample size formula calculates how many respondents you need to survey to get statistically significant results based on your population size, desired margin of error, and confidence level.

2. How Does the Calculator Work?

The calculator uses the SurveyMonkey sample size formula:

\[ \text{Sample Size} = \frac{\text{Population}}{1 + \text{Population} \times \frac{\text{Margin of Error}^2}{\text{Confidence Level}^2}} \]

Where:

\( \text{Population} \) — Total number of people in your target group
\( \text{Margin of Error} \) — Acceptable error margin (typically 5%)
\( \text{Confidence Level} \) — Statistical confidence level (typically 95%)

Explanation: The formula balances the need for accuracy (smaller margin of error) with practical constraints (population size), while accounting for the desired confidence in results.

3. Importance of Sample Size Calculation

Details: Proper sample size ensures your survey results are statistically valid and representative of your target population without wasting resources on excessive sampling.

4. Using the Calculator

Tips: Enter your total population size, desired margin of error (typically 5%), and confidence level (typically 95%). All values must be valid (population > 0, margin 0-100).

5. Frequently Asked Questions (FAQ)

Q1: What's a good margin of error for surveys?
A: For most purposes, 5% is acceptable. For more precise results, use 3% or lower (requires larger sample size).

Q2: What confidence level should I use?
A: 95% is standard for most research. Use 90% for less critical surveys or 99% for high-stakes research.

Q3: Does population size matter for large populations?
A: For populations >100,000, the sample size becomes nearly constant for a given margin/confidence.

Q4: What if my response rate is low?
A: Increase your initial sample size to account for expected non-responses (e.g., if you expect 50% response rate, double the calculated sample size).

Q5: Are there other sample size formulas?
A: Yes, different formulas exist for different types of studies (e.g., clinical trials, A/B tests), but this is standard for surveys.