CSAT & Customer Effort Score Calculator

How it works

CSAT % = responses in the satisfied boxes (top two; top three on 1–10) ÷ all responses × 100; CSAT mean = Σ(score × count) ÷ n; top-box % = top score ÷ n; CES = Σ(score × count) ÷ n on the effort question; low-effort share = easy answers ÷ n; margin of error = z √(p(1−p)/n) with z = 1.645, 1.96 or 2.576; Wilson interval = (p + z²/2n ± z√(p(1−p)/n + z²/4n²)) ÷ (1 + z²/n); change test: z = (p₁ − p₂) ÷ √(p̄(1−p̄)(1/n₁ + 1/n₂)); extra satisfied responses for target t = (t·n − satisfied) ÷ (1 − t)

CSAT asks how satisfied a customer is with a specific interaction and is usually reported as the share choosing the top two boxes, with the mean as a secondary view — transactional, fast to move, and the standard for support and post-purchase surveys. Enter it as counts per score, paste the individual ratings from a survey export, or just type how many were satisfied out of the total. A strict top-box score and your own cut-off are available under More options, and the distribution table and chart show where answers cluster. Customer effort score asks how easy the company made it to get the job done; the CES 2.0 version uses a seven-point agreement scale, and older surveys use 1–5 (sometimes with 1 meaning the least effort). Gartner/CEB research found effort predicts repurchase and word of mouth better than satisfaction, because delighted customers stay loyal only slightly more than merely satisfied ones, while customers who had to struggle overwhelmingly defect. Read the two together: high satisfaction with high effort is a hidden churn risk, low satisfaction despite low effort points at the product rather than the process. Small samples and low response rates make both scores noisy, so the calculator reports the margin of error and a Wilson confidence interval, and with last period’s score and sample size it tests whether a change is real or likely noise.

Worked example

820 CSAT responses on a 1–5 scale (18, 32, 90, 260, 420) with 680 scoring 4 or 5 give 680 ÷ 820 = 82.9% satisfied, a mean of 4.26 and a 51.2% top-box score — good, ±2.6 points at 95% (interval 80.2% to 85.3%). 717 CES responses average 5.52 out of 7 with 80.9% low-effort and 9.3% high-effort: satisfaction and effort agree, and the 13.7% response rate is adequate. If last quarter scored 80% on 700 responses, the 2.9-point rise gives z = 1.47 — not significant at 95%. Reaching 85% would take 114 more satisfied responses with no new unhappy ones.

Frequently asked questions