diff --git a/pdb-api/src/main/java/org/lucares/pdb/api/Tags.java b/pdb-api/src/main/java/org/lucares/pdb/api/Tags.java
index 6fb8174..13d3699 100644
--- a/pdb-api/src/main/java/org/lucares/pdb/api/Tags.java
+++ b/pdb-api/src/main/java/org/lucares/pdb/api/Tags.java
@@ -1,5 +1,6 @@
 package org.lucares.pdb.api;
 
+import java.nio.charset.StandardCharsets;
 import java.util.Arrays;
 import java.util.Collection;
 import java.util.List;
@@ -14,6 +15,7 @@ import java.util.regex.Pattern;
 public class Tags {
 
 	public static StringCompressor STRING_COMPRESSOR = null;
+	public static final byte[] EMPTY_BYTES = new byte[0];
 	public static final Tags EMPTY = new Tags();
 
 	public static final String KEY_VALUE_SEPARATOR = "-";
@@ -29,10 +31,10 @@ public class Tags {
 
 	private static final Pattern EXTRACT_TAGS_PATTERN = Pattern.compile(REGEX_STORAGE_FILE);
 
-	private final String filename;
+	private final byte[] filenameBytes;
 
 	public Tags() {
-		filename = "";
+		filenameBytes = EMPTY_BYTES;
 	}
 
 	public Tags(final String filename) {
@@ -42,11 +44,13 @@ public class Tags {
 		// after the $ is incremented
 		// We only take the part until the $.
 		final int end = filename.indexOf(KEY_VALUE_END_SEPARATOR);
+		final String normalizedFilename;
 		if (end >= 0) {
-			this.filename = filename.substring(0, end);
+			normalizedFilename = filename.substring(0, end);
 		} else {
-			this.filename = filename;
+			normalizedFilename = filename;
 		}
+		this.filenameBytes = normalizedFilename.getBytes(StandardCharsets.UTF_8);
 	}
 
 	public static Tags create(final Collection<Tag> tags) {
@@ -77,7 +81,7 @@ public class Tags {
 	}
 
 	public String getFilename() {
-		return filename;
+		return new String(this.filenameBytes, StandardCharsets.UTF_8);
 	}
 
 	public String getValue(final String key) {
@@ -93,6 +97,7 @@ public class Tags {
 
 	private SortedSet<Tag> toTags() {
 		final SortedSet<Tag> result = new TreeSet<>(TagByKeyComparator.INSTANCE);
+		final String filename = new String(this.filenameBytes, StandardCharsets.UTF_8);
 		final Matcher matcher = EXTRACT_TAGS_PATTERN.matcher(filename);
 
 		if (matcher.find()) {
@@ -160,14 +165,14 @@ public class Tags {
 
 	@Override
 	public String toString() {
-		return "Tags [filename=" + filename + "]";
+		return "Tags [filename=" + getFilename() + ", tags=" + toTags() + "]";
 	}
 
 	@Override
 	public int hashCode() {
 		final int prime = 31;
 		int result = 1;
-		result = prime * result + ((filename == null) ? 0 : filename.hashCode());
+		result = prime * result + Arrays.hashCode(filenameBytes);
 		return result;
 	}
 
@@ -180,10 +185,7 @@ public class Tags {
 		if (getClass() != obj.getClass())
 			return false;
 		final Tags other = (Tags) obj;
-		if (filename == null) {
-			if (other.filename != null)
-				return false;
-		} else if (!filename.equals(other.filename))
+		if (!Arrays.equals(filenameBytes, other.filenameBytes))
 			return false;
 		return true;
 	}
@@ -204,7 +206,7 @@ public class Tags {
 	}
 
 	public boolean isEmpty() {
-		return filename == null || filename.length() == 0;
+		return filenameBytes == null || filenameBytes.length == 0;
 	}
 
 	public static Tags create(final String filename) {