diff --git a/CHANGELOG.md b/CHANGELOG.md
index 72f9c42d..08fe041c 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,7 @@
 # Changelog
 
+## Unreleased
+
 ## 1.18.2 - 2021-07-23
 ### Additions
 - [bbc] add `gallery` and `programme` extractors ([#1706](https://github.com/mikf/gallery-dl/issues/1706))
diff --git a/gallery_dl/util.py b/gallery_dl/util.py
index 34621385..2c0fae60 100644
--- a/gallery_dl/util.py
+++ b/gallery_dl/util.py
@@ -97,6 +97,17 @@ def generate_token(size=16):
     return binascii.hexlify(data).decode()
 
 
+def format_value(value, unit="B", suffixes="kMGTPEZY"):
+    value = format(value)
+    value_len = len(value)
+    index = value_len - 4
+    if index >= 0:
+        offset = (value_len - 1) % 3 + 1
+        return (value[:offset] + "." + value[offset:offset+2] +
+                suffixes[index // 3] + unit)
+    return value + unit
+
+
 def combine_dict(a, b):
     """Recursively combine the contents of 'b' into 'a'"""
     for key, value in b.items():
diff --git a/gallery_dl/version.py b/gallery_dl/version.py
index fbb4e5be..6e790462 100644
--- a/gallery_dl/version.py
+++ b/gallery_dl/version.py
@@ -6,4 +6,4 @@
 # it under the terms of the GNU General Public License version 2 as
 # published by the Free Software Foundation.
 
-__version__ = "1.18.2"
+__version__ = "1.18.3-dev"
diff --git a/test/test_util.py b/test/test_util.py
index 2d574da8..7a31ebbd 100644
--- a/test/test_util.py
+++ b/test/test_util.py
@@ -532,6 +532,22 @@ class TestOther(unittest.TestCase):
         self.assertEqual(len(token), 80 * 2)
         self.assertRegex(token, r"^[0-9a-f]+$")
 
+    def test_format_value(self):
+        self.assertEqual(util.format_value(0)         , "0B")
+        self.assertEqual(util.format_value(1)         , "1B")
+        self.assertEqual(util.format_value(12)        , "12B")
+        self.assertEqual(util.format_value(123)       , "123B")
+        self.assertEqual(util.format_value(1234)      , "1.23kB")
+        self.assertEqual(util.format_value(12345)     , "12.34kB")
+        self.assertEqual(util.format_value(123456)    , "123.45kB")
+        self.assertEqual(util.format_value(1234567)   , "1.23MB")
+        self.assertEqual(util.format_value(12345678)  , "12.34MB")
+        self.assertEqual(util.format_value(123456789) , "123.45MB")
+        self.assertEqual(util.format_value(1234567890), "1.23GB")
+
+        self.assertEqual(util.format_value(123   , "B/s"), "123B/s")
+        self.assertEqual(util.format_value(123456, "B/s"), "123.45kB/s")
+
     def test_combine_dict(self):
         self.assertEqual(
             util.combine_dict({}, {}),