diff --git a/src/main/java/illgner/ch/createzip/SplitZipWriter.java b/src/main/java/illgner/ch/createzip/SplitZipWriter.java
index fe6349d..c926962 100755
--- a/src/main/java/illgner/ch/createzip/SplitZipWriter.java
+++ b/src/main/java/illgner/ch/createzip/SplitZipWriter.java
@@ -85,8 +85,10 @@ public class SplitZipWriter implements Closeable {
             switchOutputFile();
         }
         LOG.info("Writing file {} to zip", path);
+        long entryStartBytes = countingOutputStream.getCount();
         zipOutputStream.putNextEntry(new ZipEntry(path));
-        bytesWritten += IOUtils.copyLarge(inputStream, zipOutputStream);
+        IOUtils.copyLarge(inputStream, zipOutputStream);
+        bytesWritten += countingOutputStream.getCount() - entryStartBytes;
         zipOutputStream.closeEntry();
     }