SAMPLE SIZE
CALCULATOR
Estimate how many responses you need before launching a survey, poll, or research study.
Calculator Inputs
How to Read It
More precise, but usually much more expensive to collect.
A common balance between precision and effort for general surveys.
Faster to collect, but the interval around each estimate will be much wider.
Survey Planning
Sample Size
This estimate uses the standard z-score formula for proportions and applies the finite population correction when you enter a known audience size.
Export / Save
Download the planning snapshot as transparent PNG or JPG
WHERE SAMPLE PLANNING HELPS
Use it before fieldwork starts so your survey plan is realistic and defendable.
Marketing Research
- • Campaign lift surveys
- • Brand recall studies
- • Creative testing panels
- • Audience sentiment checks
Customer Feedback
- • NPS sampling plans
- • Onboarding feedback
- • Feature satisfaction checks
- • Support quality reviews
Education & Training
- • Course evaluations
- • Workshop feedback targets
- • Student pulse surveys
- • Program effectiveness studies
Research Design
- • Pilot study sizing
- • Fieldwork budgeting
- • Quota planning
- • Stakeholder approvals
Operations
- • Employee pulse checks
- • Process rollout validation
- • Internal benchmark surveys
- • Team health measurement
Community Surveys
- • Member feedback targets
- • Event follow-up surveys
- • Cohort satisfaction studies
- • Volunteer program check-ins
WHY USE THIS SAMPLE SIZE CALCULATOR?
Confidence-Based Planning
Choose 90%, 95%, or 99% confidence and size the sample accordingly
Margin Targets
Estimate how many responses you need for a 3%, 5%, or custom error target
Population Correction
Account for finite audiences when you know the full population size
Live Result Board
Update assumptions and see the required sample count change instantly
Export Ready
Download a clean planning snapshot to share with stakeholders or clients
No Login Needed
Open the calculator directly in the browser without creating an account