diff --git a/src/main/kotlin/kr/co/vividnext/sodalive/chat/character/service/RankingWindowCalculator.kt b/src/main/kotlin/kr/co/vividnext/sodalive/chat/character/service/RankingWindowCalculator.kt
index 0767e7d..8057d85 100644
--- a/src/main/kotlin/kr/co/vividnext/sodalive/chat/character/service/RankingWindowCalculator.kt
+++ b/src/main/kotlin/kr/co/vividnext/sodalive/chat/character/service/RankingWindowCalculator.kt
@@ -19,6 +19,7 @@ object RankingWindowCalculator {
     private val ZONE: ZoneId = ZoneOffset.UTC
     private const val BOUNDARY_HOUR = 20 // 20:00:00 UTC
 
+    @JvmStatic
     fun now(prefix: String = "popular-chat-character"): RankingWindow {
         val now = ZonedDateTime.now(ZONE)
         val todayBoundary = now.toLocalDate().atTime(BOUNDARY_HOUR, 0, 0).atZone(ZONE)