What means polulation size?
The population is the total number of people to whom one wants to draw conclusions with a survey or study with a sample. Accordingly, the population is the total number of all persons who would be eligible for a survey or study. Since the population is usually too large, one does not survey all persons of the population, but only a sample. In this sample calculator, this information is required to be able to calculate the size of the sample. For example, the population can be the number of people in a country, the number of households in a city or all people who have a certain characteristic, such as driving a car or voting for a certain party.

What means Proportion of characteristics?
It is important to consider the proportion of characteristics when calculating a sample size for a survey or research study because the proportion can affect the accuracy of the results. The proportion of characteristics refers to the expected prevalence of a particular characteristic within the population being studied. For example, if you are conducting a survey to understand the proportion of people who support a certain political candidate, the proportion of characteristics would be the expected proportion of people who support that candidate within the overall population.

If the sample size is not calculated correctly, it can lead to a biased sample that does not accurately represent the population. For example, if the proportion of a particular characteristic in the population is very different from the proportion in the sample, it could lead to inaccurate conclusions being drawn from the study. On the other hand, if the proportion of a characteristic in the sample is similar to the proportion in the population, it increases the likelihood that the results of the study are representative of the population as a whole.

So enter the expected frequency of the characteristic in this field.

If you do not know or do not want to estimate the proportion of the characteristics, use our simple sample size calculator.

→ Simple Sample Size Calculator

What means confidence level?
In the context of sample size calculation, confidence level refers to the degree of certainty that researchers want to have in the results of a study. When calculating the sample size for a survey or research study, researchers often specify a desired confidence level, which is usually expressed as a percentage.

The confidence level is used to determine the sample size needed to achieve a certain level of accuracy in the results. A higher confidence level requires a larger sample size, because a higher level of confidence means that researchers want to be more certain that the results are accurate. On the other hand, a lower confidence level can be achieved with a smaller sample size, because a lower level of confidence means that researchers are willing to accept a higher level of uncertainty in the results.

For example, if researchers want to have a 95% confidence level in the results of a study, they would need a larger sample size than if they were only looking for a 90% confidence level. This is because a 95% confidence level means that the researchers want to be more certain that the results are accurate, so they need a larger sample to increase the likelihood that the results will be representative of the population.

So enter in this field what exactly the result of the study should be

What means margin of error?
The margin of error is an important factor in calculating a sample because it indicates how accurate the results of a survey or study should be. The margin of error indicates by how many percent or percentage points the results may deviate from the actual size of the population. The smaller the margin of error, the more accurate the results of the study and the larger the sample to be calculated.

So, in the margin of error field, specify by how many percent the result may deviate