diff --git a/tools/analyze-dump-sort.py b/tools/analyze-dump-sort.py
new file mode 100755
index 0000000000..015027ad4b
--- /dev/null
+++ b/tools/analyze-dump-sort.py
@@ -0,0 +1,78 @@
+#!/usr/bin/python
+# SPDX-License-Identifier: LGPL-2.1-or-later
+
+"""
+A helper to compare 'systemd-analyze dump' outputs.
+
+systemd-analyze dump >/var/tmp/dump1
+(reboot)
+tools/analyze-dump-sort.py /var/tmp/dump1 → this does a diff from dump1 to current
+
+systemd-analyze dump >/var/tmp/dump2
+tools/analyze-dump-sort.py /var/tmp/{dump1,dump2} → this does a diff from dump1 to dump2
+"""
+
+import argparse
+import tempfile
+import subprocess
+
+def sort_dump(sourcefile, destfile=None):
+    if destfile is None:
+        destfile = tempfile.NamedTemporaryFile('wt')
+
+    units = {}
+    unit = []
+
+    same = []
+
+    for line in sourcefile:
+        line = line.rstrip()
+
+        header = line.split(':')[0]
+        if 'Timestamp' in header or 'Invocation ID' in header or 'PID' in header:
+            line = header + ': …'
+
+        if line.startswith('->'):
+            if unit:
+                units[unit[0]] = unit
+            unit = [line]
+        elif line.startswith('\t'):
+            assert unit
+
+            if same and same[0].startswith(header):
+                same.append(line)
+            else:
+                unit.extend(sorted(same, key=str.lower))
+                same = [line]
+        else:
+            print(line, file=destfile)
+
+    if unit:
+        units[unit[0]] = unit
+
+    for unit in sorted(units.values()):
+        print('\n'.join(unit), file=destfile)
+
+    destfile.flush()
+    return destfile
+
+def parse_args():
+    p = argparse.ArgumentParser(description=__doc__)
+    p.add_argument('one')
+    p.add_argument('two', nargs='?')
+    p.add_argument('--user', action='store_true')
+    return p.parse_args()
+
+if __name__ == '__main__':
+    opts = parse_args()
+
+    one = sort_dump(open(opts.one))
+    if opts.two:
+        two = sort_dump(open(opts.two))
+    else:
+        user = ['--user'] if opts.user else []
+        two = subprocess.run(['systemd-analyze', 'dump', *user],
+                             capture_output=True, text=True, check=True)
+        two = sort_dump(two.stdout.splitlines())
+    with subprocess.Popen(['diff', '-U10', one.name, two.name], stdout=subprocess.PIPE) as diff:
+        subprocess.Popen(['less'], stdin=diff.stdout)