Index: /applications/editors/josm/plugins/pmtiles/src/main/java/org/openstreetmap/josm/plugins/pmtiles/lib/PMTiles.java
===================================================================
--- /applications/editors/josm/plugins/pmtiles/src/main/java/org/openstreetmap/josm/plugins/pmtiles/lib/PMTiles.java	(revision 36155)
+++ /applications/editors/josm/plugins/pmtiles/src/main/java/org/openstreetmap/josm/plugins/pmtiles/lib/PMTiles.java	(revision 36156)
@@ -14,6 +14,4 @@
 import java.util.zip.InflaterInputStream;
 
-import jakarta.json.Json;
-import jakarta.json.JsonObject;
 import org.apache.commons.compress.compressors.brotli.BrotliCompressorInputStream;
 import org.apache.commons.compress.compressors.gzip.GzipCompressorInputStream;
@@ -21,4 +19,7 @@
 import org.openstreetmap.josm.plugins.pmtiles.lib.internal.HeaderParser;
 import org.openstreetmap.josm.tools.Utils;
+
+import jakarta.json.Json;
+import jakarta.json.JsonObject;
 
 /**
@@ -273,5 +274,5 @@
             }
         }
-        var request = HttpRequest.newBuilder(location).header("Range", "bytes=" + start + "-" + (start + length))
+        var request = HttpRequest.newBuilder(location).header("Range", "bytes=" + start + "-" + (start + length - 1))
                 .header("User-Agent", "JOSM PMTiles v1").GET().build();
         try {