Planning surveys is mostly math and mostly realism: how many completed responses you need, what response rate you can reasonably expect, and how many invites you must send to hit the target.
There are two calculations that matter: how to compute response rate after a campaign, and how to estimate invites before you send anything.
Use this when the survey is complete and you want to report performance.
Response rate (%) = (Completed surveys ÷ Invitations sent) × 100
Tip: If many invites bounce or aren’t delivered, track “valid invitations” separately so you can compare campaigns more fairly.
Use this before you send the survey so you can choose a realistic sample.
Invites needed = Target responses ÷ Expected response rate (decimal)
Example: 200 responses at 25% → 200 ÷ 0.25 = 800 invites
Always round invites up, and consider adding a buffer if your audience list includes stale emails or low-intent users.
These two metrics answer different questions:
Low response rate usually means invite/channel issues. Low completion rate usually means survey length, clarity, or mobile UX problems.
A “good” response rate depends on list quality, relationship, channel, incentives, and survey length. Still, it helps to start with a planning range so you don’t under-invite.
If you have historical data, use your own baseline instead of generic benchmarks.
If you expect 50% response rate from an email list that hasn’t engaged in months, the plan is probably wrong. In that case, either increase invites, shorten the survey, add an incentive, or change channel (e.g., in-app).
Use this when you’re planning a new survey and don’t want to overthink the stats. It helps you choose a target response count and prevent common planning mistakes.
What will change based on the survey? Examples: pick the top 3 UX issues, validate pricing sensitivity, or measure support effort.
For directional insights, many teams aim for 50–200 responses per key segment. For statistical precision, use a sample size calculator and then plan invites using response rate.
Tip: If you want to compare two segments (e.g., new vs returning customers), plan for enough responses in each segment.
If uncertain, start with 10–20% for email and adjust based on your relationship and incentives. It’s better to over-invite and stop early than to under-invite and miss your target.
Invites = TargetResponses ÷ ExpectedRate
Add a buffer (5–20%) if you expect bounced emails, spam filtering, or weak list hygiene.