diff --git a/docs/manual/common-usage.txt b/docs/manual/common-usage.txt
index 6a6ec19552..7af8d54a64 100644
--- a/docs/manual/common-usage.txt
+++ b/docs/manual/common-usage.txt
@@ -326,6 +326,9 @@ to further control the generated graph. Accepted options are:
   contributing less than 1% are grouped under _Others_. Accepted values
   are in the range `[0.0..1.0]`.
 
+* `--iec`, `--binary`, `--si`, `--decimal`, to use IEC (binary, powers
+  of 1024) or SI (decimal, powers of 1000; the default) prefixes.
+
 .Note
 The collected filesystem size data is only meaningful after a complete
 clean rebuild. Be sure to run +make clean all+ before using +make
diff --git a/support/scripts/size-stats b/support/scripts/size-stats
index d197ac154b..040f4017f8 100755
--- a/support/scripts/size-stats
+++ b/support/scripts/size-stats
@@ -35,6 +35,7 @@ except ImportError:
 
 
 class Config:
+    iec = False
     size_limit = 0.01
     colors = ['#e60004', '#009836', '#2e1d86', '#ffed00',
               '#0068b5', '#f28e00', '#940084', '#97c000']
@@ -132,8 +133,12 @@ def build_package_size(filesdict, builddir):
 #
 def draw_graph(pkgsize, outputf):
     def size2string(sz):
-        divider = 1000.0
-        prefixes = ['', 'k', 'M', 'G', 'T']
+        if Config.iec:
+            divider = 1024.0
+            prefixes = ['', 'Ki', 'Mi', 'Gi', 'Ti']
+        else:
+            divider = 1000.0
+            prefixes = ['', 'k', 'M', 'G', 'T']
         while sz > divider and len(prefixes) > 1:
             prefixes = prefixes[1:]
             sz = sz/divider
@@ -238,6 +243,21 @@ def gen_packages_csv(pkgsizes, outputf):
             wr.writerow([pkg, size, "%.1f" % (float(size) / total * 100)])
 
 
+#
+# Our special action for --iec, --binary, --si, --decimal
+#
+class PrefixAction(argparse.Action):
+    def __init__(self, option_strings, dest, **kwargs):
+        for key in ["type", "nargs"]:
+            if key in kwargs:
+                raise ValueError('"{}" not allowed'.format(key))
+        super(PrefixAction, self).__init__(option_strings, dest, nargs=0,
+                                           type=bool, **kwargs)
+
+    def __call__(self, parser, namespace, values, option_string=None):
+        setattr(namespace, self.dest, option_string in ["--iec", "--binary"])
+
+
 def main():
     parser = argparse.ArgumentParser(description='Draw size statistics graphs')
 
@@ -249,11 +269,16 @@ def main():
                         help="CSV output file with file size statistics")
     parser.add_argument("--package-size-csv", '-p', metavar="PKG_SIZE_CSV",
                         help="CSV output file with package size statistics")
+    parser.add_argument("--iec", "--binary", "--si", "--decimal",
+                        action=PrefixAction,
+                        help="Use IEC (binary, powers of 1024) or SI (decimal, "
+                             "powers of 1000, the default) prefixes")
     parser.add_argument("--size-limit", "-l", type=float,
                         help='Under this size ratio, files are accounted to ' +
                              'the generic "Other" package. Default: 0.01 (1%%)')
     args = parser.parse_args()
 
+    Config.iec = args.iec
     if args.size_limit is not None:
         if args.size_limit < 0.0 or args.size_limit > 1.0:
             parser.error("--size-limit must be in [0.0..1.0]")