diff --git a/src/modules/reader/utils/Reader.utils.ts b/src/modules/reader/utils/Reader.utils.ts
index 7ec12721..7503b82c 100644
--- a/src/modules/reader/utils/Reader.utils.ts
+++ b/src/modules/reader/utils/Reader.utils.ts
@@ -104,7 +104,7 @@ export const getChapterIdsForDownloadAhead = (
     }
 
     const isDownloadAheadEnabled = !!downloadAheadLimit;
-    const inDownloadRange = currentPageIndex / chapterUpToDateData.pageCount > 0.25;
+    const inDownloadRange = (currentPageIndex + 1) / chapterUpToDateData.pageCount > 0.25;
     const shouldCheckDownloadAhead = isDownloadAheadEnabled && chapterUpToDateData.isDownloaded && inDownloadRange;
     if (!shouldCheckDownloadAhead) {
         return [];