Confidence interval calculator

Confidence interval is the plus-or-minus figure which is one of the indications of how your findings are the same as the opinions of the whole population. For example, you have a confidence interval of 4 and 32% percent of your respondents answered "no" to the question if they would buy your product again. In that case you can be "sure" that if you had asked the question to the entire relevant population between 28% (32-4) and 36% (32+4) would have picked that answer. The following tool can be used to calculate what confidence interval your research project has. An explanation of the used terms can be found by clicking on them.


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