Your August shelf
is decided in June

For sunscreen, search moves before sales — which is why you watch June, not August.

On Naver DataLab, sunscreen search surges in Apr–May and peaks in June. Korea's summer search boiling first reads as a lead indicator for the US summer peak, where the same UV-protection demand circulates. On Amazon US, 'korean sunscreen' is among the thickest single summer keywords, and entry happens through the 'korean + spf + ingredient keyword' combination.
The exact monthly volume, related-term frequency, and entry-keyword priority are laid out in the full report.

* Search volume is a public Helium10 Cerebro / Naver DataLab index, and there is a lag between search timing and actual sales (co-search ≠ same-session purchase).

Even when search comes in, no reviews means no conversion to sales.

Summer traffic floods in during August, but if your listing is empty of reviews by then, that traffic leaks to competitors who already have them. That's why a new listing must lay down an early review asset before the traffic arrives.
How much review count and star rating lift purchase conversion — with figures from public research — is in the full report with sources attached.

* The 5-review effect is the 'up to' upper bound from Spiegel·Northwestern (2017); the star-rating effect is an Emplicit (2025) estimate (confidence: medium). They come from different sources and are not chained as one causal claim.

A week-by-week June lead-time calendar, drawn backward from the August peak.

To win the August shelf, slice June into weeks and count backward. Slip a single week and your August exposure disappears entirely.
· June, week 1 — Start influencer outreach. Casting → shooting → publishing takes several weeks, so this week is the deadline for August exposure. (channel: influencer/UGC)
· June, week 2 — Kick off the review campaign. Korean reviews take about 14 days, so starting this week completes the asset by early July. (channel: review campaign)
· June, week 3 — Plant 'korean + spf + ingredient' entry keywords in your listing and content. Search entry takes time to index. (channel: Amazon listing/search)
· June, week 4 — Align reviews, UGC, and keywords on one listing. Audit traffic in July, enter the August peak.

The 100-review base is common to every report; what's specific here is which week of June you must start those 100 to land in August — the week-level timing.
Korea was the world's #2 cosmetics exporter in 2025 ($11.4B), and the US is its largest market ($2.2B) (Korea Herald). Demand is already large — the question is whether your shelf has reviews in August.