diff --git a/lib/Epub/Epub.cpp b/lib/Epub/Epub.cpp
index 8b4bb9a..fcd1615 100644
--- a/lib/Epub/Epub.cpp
+++ b/lib/Epub/Epub.cpp
@@ -150,6 +150,18 @@ bool Epub::load() {
     return false;
   }
 
+  // determine size of spine items
+  size_t spineItemsCount = getSpineItemsCount();
+  size_t spineItemsSize = 0;
+  for (size_t i = 0; i < spineItemsCount; i++) {
+    std::string spineItem = getSpineItem(i);
+    size_t s = 0;
+    getItemSize(spineItem, &s);
+    spineItemsSize += s;
+    cumulativeSpineItemSize.emplace_back(spineItemsSize);
+  }
+  Serial.printf("[%lu] [EBP] Book size: %u\n", millis(), spineItemsSize);
+
   Serial.printf("[%lu] [EBP] Loaded ePub: %s\n", millis(), filepath.c_str());
 
   return true;
@@ -257,6 +269,8 @@ bool Epub::getItemSize(const std::string& itemHref, size_t* size) const {
 
 int Epub::getSpineItemsCount() const { return spine.size(); }
 
+size_t Epub::getCumulativeSpineItemSize(const int spineIndex) const { return cumulativeSpineItemSize.at(spineIndex); }
+
 std::string& Epub::getSpineItem(const int spineIndex) {
   if (spineIndex < 0 || spineIndex >= spine.size()) {
     Serial.printf("[%lu] [EBP] getSpineItem index:%d is out of range\n", millis(), spineIndex);
diff --git a/lib/Epub/Epub.h b/lib/Epub/Epub.h
index 765eacc..d06fa31 100644
--- a/lib/Epub/Epub.h
+++ b/lib/Epub/Epub.h
@@ -20,6 +20,8 @@ class Epub {
   std::string filepath;
   // the spine of the EPUB file
   std::vector<std::pair<std::string, std::string>> spine;
+  // the file size of the spine items (proxy to book progress)
+  std::vector<size_t> cumulativeSpineItemSize;
   // the toc of the EPUB file
   std::vector<EpubTocEntry> toc;
   // the base path for items in the EPUB file
@@ -51,7 +53,8 @@ class Epub {
   bool getItemSize(const std::string& itemHref, size_t* size) const;
   std::string& getSpineItem(int spineIndex);
   int getSpineItemsCount() const;
-  EpubTocEntry& getTocItem(int tocTndex);
+  size_t getCumulativeSpineItemSize(const int spineIndex) const;
+  EpubTocEntry& getTocItem(int tocIndex);
   int getTocItemsCount() const;
   int getSpineIndexForTocIndex(int tocIndex) const;
   int getTocIndexForSpineIndex(int spineIndex) const;
diff --git a/src/screens/EpubReaderScreen.cpp b/src/screens/EpubReaderScreen.cpp
index 4e13f3d..6b4855e 100644
--- a/src/screens/EpubReaderScreen.cpp
+++ b/src/screens/EpubReaderScreen.cpp
@@ -324,8 +324,24 @@ void EpubReaderScreen::renderContents(std::unique_ptr<Page> page) {
 
 void EpubReaderScreen::renderStatusBar() const {
   constexpr auto textY = 776;
+
+  // Calculate progress in book
+  size_t prevChapterSize = epub->getCumulativeSpineItemSize(currentSpineIndex - 1);
+  size_t curChapterSize = epub->getCumulativeSpineItemSize(currentSpineIndex) - prevChapterSize;
+  size_t bookSize = epub->getCumulativeSpineItemSize(epub->getSpineItemsCount() - 1);
+  size_t sectionProgSize =
+      static_cast<size_t>(static_cast<float>(section->currentPage) / section->pageCount * curChapterSize);
+  float bookProgress = static_cast<float>(prevChapterSize + sectionProgSize) / bookSize * 100.0;
+  char bookProgressStr[6] = "--.-";
+std:
+  snprintf(bookProgressStr, 6, "%.1f", bookProgress);
+  // Serial.printf("[%lu] [EBP] prevChapterSize: %u bookSize: %u sectionProgSize: %u bookSize:%u Book progress: %s
+  // %%\n", millis(),
+  //     prevChapterSize, bookSize, sectionProgSize, bookSize, bookProgressStr);
+
   // Right aligned text for progress counter
-  const std::string progress = std::to_string(section->currentPage + 1) + " / " + std::to_string(section->pageCount);
+  const std::string progress = std::to_string(section->currentPage + 1) + "/" + std::to_string(section->pageCount) +
+                               "  " + bookProgressStr + "%";
   const auto progressTextWidth = renderer.getTextWidth(SMALL_FONT_ID, progress.c_str());
   renderer.drawText(SMALL_FONT_ID, GfxRenderer::getScreenWidth() - marginRight - progressTextWidth, textY,
                     progress.c_str());