This free toolbox brings together four practical calculators that professional researchers use every day. Quickly check sample sizes, simulate weighting, test significance, and forecast survey drop-off — all in one place. Note that these tools are easiest to use on desktop / laptop.
Enter your expected proportion, margin of error, and confidence level to instantly calculate the recommended sample size. The tool adjusts for finite populations automatically.
See how sample vs. target distributions affect weighting. Explore design effects, effective sample size, and how weighting shifts an outcome measure.
Compare two groups to test whether the difference between their proportions is statistically significant. Switch between count or percentage inputs and choose your confidence level.
Estimate survey completion rates based on question mix, device share, incentives, and invite-to-start rates. Useful for planning length and incentive strategies.