diff --git a/gepi/gepi-core/src/main/java/de/julielab/gepi/core/services/GeneIdService.java b/gepi/gepi-core/src/main/java/de/julielab/gepi/core/services/GeneIdService.java
index 4059fb10..ead47bca 100644
--- a/gepi/gepi-core/src/main/java/de/julielab/gepi/core/services/GeneIdService.java
+++ b/gepi/gepi-core/src/main/java/de/julielab/gepi/core/services/GeneIdService.java
@@ -296,7 +296,7 @@ public Future<IdConversionResult> convert(Stream<String> stream, IdType to) {
         return CompletableFuture.supplyAsync(() -> {
             long time = System.currentTimeMillis();
             final Multimap<IdType, String> idsByType = determineIdTypes(stream);
-            log.debug("Starting to convert {} input IDs for GePI retrieval.");
+            log.debug("Starting to convert {} input IDs for GePI retrieval.", idsByType.values().size());
             final List<Future<IdConversionResult>> convertedIds = new ArrayList<>();
             for (IdType from : idsByType.keySet()) {
                 final Collection<String> sourceIds = idsByType.get(from);