diff --git a/src/restic/prune.py b/src/restic/prune.py
index 8045dc2..8b94a9d 100644
--- a/src/restic/prune.py
+++ b/src/restic/prune.py
@@ -12,7 +12,7 @@ from restic.console import console, logger
 from restic.loki import send_to_loki
 
 field_regex = re.compile(
-    r'^(?P<name>[\w ]+):\s+(?P<blobs>\d+) blobs \/ (?P<size>\d+(\.\d+)? (M|G)iB)', re.MULTILINE
+    r'^(?P<name>[\w ]+):\s+(?P<blobs>\d+) blobs \/ (?P<size>\d+(\.\d+)? (?:Mi|Gi)?B)', re.MULTILINE
 )