Amazon exposes ad click-through rate in the advertising console, but never surfaces true organic click-through rate anywhere in Seller Central. Amazon Search Query Performance (SQP) Report can be exported to a spreadsheet to back-calculate it manually: for each search term, organic CTR = brand clicks ÷ brand impressions.
This is described as the only available way to obtain that number. Once calculated, track it over time per priority term to see whether organic CTR is trending up or down — a leading indicator distinct from the ad-side formulas in PPC Efficiency Metric Formulas (ACOS, CTR, CVR, CPC), since it isolates organic thumbnail/title performance from paid placement effects.
Export the SQP report to a spreadsheet and add a column dividing brand clicks by brand impressions per search term — this is the only way to see true organic (non-ad) click-through rate, since Amazon exposes ad CTR directly but never surfaces organic CTR on its own. Track that ratio over time per priority search term to catch organic CTR drift outside of paid performance.