This Slovin Formula Calculator computes the minimum sample size for your study. You only need to enter the size of your target population (N) and the margin of error (e) as a decimal to get instant results. The calculator also provides a step-by-step explanation of how to apply Slovin’s formula manually to compute the required sample size (n).
Step-by-Step Explanation
What is Slovin’s Formula?
Slovin’s formula is one of the most common sample size determination formulas in research. The formula was founded by Slovin in 1960 and later popularized by Taro Yamane in 1967. Due to this, researchers often find it difficult to differentiate between these two formulas.
The Slovin’s formula is n = N / (1 + N·e²)
Where:
- n is the minimum sample size you wish to calculate
- N is the size of your target population
- e is the margin of error, often expressed as a decimal. The margin of error basically represents the acceptable level of inaccuracy in your study.
Note. Using either Slovin’s formula or Yamane’s formula will yield the same sample size since they both have the same structure. The only difference lies in historical attribution and usage.
While the two formulas share a similar structure, researchers often cite Yamane’s formula (1967) more frequently in academic works like dissertations and theses. This is largely due to its explicit presentation and derivation within an established academic textbook on sampling theory by Taro Yamane.
How to Use Slovin’s Sample Size Calculator
We understand that not everyone is good at math. That’s why we simplified Slovin’s formula using the calculator. We made it easier for you to calculate and learn how to compute the sample size manually. With the calculator, you can obtain the minimum sample size by following these simple steps:
- Enter the total population size (N)
- Enter the margin of error (e) as a decimal
- Click the calculate button:
The calculator will apply Slovin’s formula and display the required sample size. It will also provide a clear explanation of how to apply Slovin’s formula to determine the minimum sample size.
When Should You Use Slovin’s Formula?
Not sure how many respondents you need, but you do know your population size? That’s exactly where Slovin’s formula comes in handy.
You should use Slovin’s formula when:
- The population size is known
- You are using simple random sampling
- You lack prior information about population variability
- The study is exploratory or descriptive in nature
- You need a quick and practical sample size estimate for a project, survey, or thesis
