diff --git a/src/renderer/index.html b/src/renderer/index.html
index c0420f4..7e082f5 100644
--- a/src/renderer/index.html
+++ b/src/renderer/index.html
@@ -27,7 +27,7 @@
   <label>파일명 포맷</label>
   <input type="text" id="input-prefix" value="photo" placeholder="접두사" />
   <span class="format-sep">_</span>
-  <input type="number" id="input-digits" value="3" min="1" max="6" />
+  <input type="number" id="input-digits" value="4" min="1" max="6" />
   <span class="format-sep">자리 순번</span>
   <span style="color:var(--muted);font-size:12px;">→</span>
   <span id="preview-name">photo_001.jpg</span>