Precision starts with your sample size

The secret to products people love is precision. Calculate the number of respondents your study needs to turn customer feedback into a high-confidence growth strategy.

Calculate your sample size
Sample size estimate

• Population: 10,000
• Confidence: 95%
• Margin: 5%
• 370 respondents needed

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What is a sample size?

In market research and product testing, your sample size is the number of people you survey or test your product with. Instead of reaching an entire audience, researchers rely on a representative group to gather insights at a chosen confidence level and margin of error — fast, and without the cost of surveying everyone.

Three numbers, one formula

How to calculate your sample size

Enter your numbers below and Highlight returns an estimate based on the standard sample size formula used in quantitative research.

1. Population size
   The total group your study is meant to represent — your addressable market, your customer base, or a specific target segment.
2. Confidence level
   How sure you want to be that your sample reflects the full population. Most researchers work at 95%.
3. Margin of error
   How much variation you’ll accept between your sample’s results and the true population. Most researchers aim for 3–5%.

Try it yourself

Enter your population, confidence level, and margin of error to get an instant estimate.

Calculate Your Sample Size For Digital Testing

• Population Size
• Confidence Level (%)
• Margin of Error (%)
• Sample Size: 383

Common sample size mistakes to avoid

• Guessing your TAM
  Over- or underestimating your Total Addressable Market skews your confidence interval before you’ve collected a single response.
• Ignoring the margin of error
  Smaller samples carry larger margins of error. Shrink your sample without accounting for it, and you quietly erode how much you can trust the results.
• Testing the wrong people
  Respondent quality matters as much as quantity — a perfectly sized sample of the wrong audience still gives you the wrong answer.

Your number is just the start

Once you know your sample size, Highlight handles the rest — from finding the right people to getting your product into their hands.

• Define the right audience for your study
• Find and recruit respondents who match your criteria
• Handle logistics for physical and digital product tests alike

Common sample size calculator questions

• What sample size do I need for a 95% confidence level?
  It depends on your population and margin of error — for a population of 10,000 with a 5% margin of error, you’d need roughly 370 respondents.
• What is a good margin of error for market research?
  Most market researchers aim for 3–5%. The smaller the margin, the larger the sample size you’ll need.
• Does population size affect the sample size I need?
  Yes, but less than you’d think. Once a population exceeds roughly 20,000, the required sample size plateaus — there’s little difference between testing 50,000 people and 5 million.
• Is this calculator enough for product testing?
  It’s a solid starting point for digital surveys. Physical product tests bring additional considerations — shipping, usage windows, and recruitment logistics — that a sample size number alone won’t capture.