diff --git a/Documentation/btrfs-inspect-internal.rst b/Documentation/btrfs-inspect-internal.rst
index 79713c30..ccd93eb8 100644
--- a/Documentation/btrfs-inspect-internal.rst
+++ b/Documentation/btrfs-inspect-internal.rst
@@ -229,11 +229,27 @@ tree-stats [options] <device>
 
         ``Options``
 
-        -b
-                Print raw numbers in bytes.
+        -b|--raw
+                raw numbers in bytes, without the *B* suffix
 
         -t <treeid>
                 Print stats only for the given treeid.
+        --human-readable
+                print human friendly numbers, base 1024, this is the default
+
+        --iec
+                select the 1024 base for the following options, according to the IEC standard
+        --si
+                select the 1000 base for the following options, according to the SI standard
+
+        --kbytes
+                show sizes in KiB, or kB with --si
+        --mbytes
+                show sizes in MiB, or MB with --si
+        --gbytes
+                show sizes in GiB, or GB with --si
+        --tbytes
+                show sizes in TiB, or TB with --si
 
 EXIT STATUS
 -----------
diff --git a/cmds/inspect-tree-stats.c b/cmds/inspect-tree-stats.c
index 15576b04..00536581 100644
--- a/cmds/inspect-tree-stats.c
+++ b/cmds/inspect-tree-stats.c
@@ -316,7 +316,7 @@ static void timeval_subtract(struct timeval *result, struct timeval *x,
 }
 
 static int calc_root_size(struct btrfs_root *tree_root, struct btrfs_key *key,
-			  int find_inline)
+			  int find_inline, unsigned int unit_mode)
 {
 	struct btrfs_root *root;
 	struct btrfs_path path = { 0 };
@@ -385,26 +385,25 @@ out_print:
 		pr_verbose(LOG_DEFAULT, "\tTotal read time: %d s %d us\n", (int)diff.tv_sec,
 		       (int)diff.tv_usec);
 	} else {
-		pr_verbose(LOG_DEFAULT, "\tTotal size: %s\n", pretty_size(stat.total_bytes));
-		pr_verbose(LOG_DEFAULT, "\t\tInline data: %s\n", pretty_size(stat.total_inline));
+		pr_verbose(LOG_DEFAULT, "\tTotal size: %s\n", pretty_size_mode(stat.total_bytes, unit_mode));
+		pr_verbose(LOG_DEFAULT, "\t\tInline data: %s\n", pretty_size_mode(stat.total_inline, unit_mode));
 		pr_verbose(LOG_DEFAULT, "\tTotal seeks: %llu\n", stat.total_seeks);
 		pr_verbose(LOG_DEFAULT, "\t\tForward seeks: %llu\n", stat.forward_seeks);
 		pr_verbose(LOG_DEFAULT, "\t\tBackward seeks: %llu\n", stat.backward_seeks);
 		pr_verbose(LOG_DEFAULT, "\t\tAvg seek len: %s\n", stat.total_seeks ?
-			pretty_size(stat.total_seek_len / stat.total_seeks) :
-			pretty_size(0));
+			pretty_size_mode(stat.total_seek_len / stat.total_seeks, unit_mode) :
+			pretty_size_mode(0, unit_mode));
 		print_seek_histogram(&stat);
 		pr_verbose(LOG_DEFAULT, "\tTotal clusters: %llu\n", stat.total_clusters);
 		pr_verbose(LOG_DEFAULT, "\t\tAvg cluster size: %s\n",
-				pretty_size((stat.total_cluster_size /
-						stat.total_clusters)));
+				pretty_size_mode((stat.total_cluster_size /
+						  stat.total_clusters), unit_mode));
 		pr_verbose(LOG_DEFAULT, "\t\tMin cluster size: %s\n",
-				pretty_size(stat.min_cluster_size));
+				pretty_size_mode(stat.min_cluster_size, unit_mode));
 		pr_verbose(LOG_DEFAULT, "\t\tMax cluster size: %s\n",
-				pretty_size(stat.max_cluster_size));
+				pretty_size_mode(stat.max_cluster_size, unit_mode));
 		pr_verbose(LOG_DEFAULT, "\tTotal disk spread: %s\n",
-				pretty_size(stat.highest_bytenr -
-					stat.lowest_bytenr));
+				pretty_size_mode(stat.highest_bytenr - stat.lowest_bytenr, unit_mode));
 		pr_verbose(LOG_DEFAULT, "\tTotal read time: %d s %d us\n", (int)diff.tv_sec,
 		       (int)diff.tv_usec);
 	}
@@ -442,6 +441,7 @@ static const char * const cmd_inspect_tree_stats_usage[] = {
 	"Print various stats for trees",
 	"",
 	OPTLINE("-b", "raw numbers in bytes"),
+	HELPINFO_UNITS_LONG,
 	OPTLINE("-t <rootid>", "print only tree with the given rootid"),
 	NULL
 };
@@ -451,10 +451,13 @@ static int cmd_inspect_tree_stats(const struct cmd_struct *cmd,
 {
 	struct btrfs_key key = { .type = BTRFS_ROOT_ITEM_KEY };
 	struct btrfs_root *root;
+	unsigned int unit_mode;
 	int opt;
 	int ret = 0;
 	u64 tree_id = 0;
 
+	unit_mode = get_unit_mode_from_arg(&argc, argv, 0);
+
 	optind = 0;
 	while ((opt = getopt(argc, argv, "vbt:")) != -1) {
 		switch (opt) {
@@ -499,32 +502,32 @@ static int cmd_inspect_tree_stats(const struct cmd_struct *cmd,
 		pr_verbose(LOG_DEFAULT, "Calculating size of tree (%llu)\n", tree_id);
 		key.objectid = tree_id;
 		key.offset = (u64)-1;
-		ret = calc_root_size(root, &key, 1);
+		ret = calc_root_size(root, &key, 1, unit_mode);
 		goto out;
 	}
 
 	pr_verbose(LOG_DEFAULT, "Calculating size of root tree\n");
 	key.objectid = BTRFS_ROOT_TREE_OBJECTID;
-	ret = calc_root_size(root, &key, 0);
+	ret = calc_root_size(root, &key, 0, unit_mode);
 	if (ret)
 		goto out;
 
 	pr_verbose(LOG_DEFAULT, "Calculating size of extent tree\n");
 	key.objectid = BTRFS_EXTENT_TREE_OBJECTID;
-	ret = calc_root_size(root, &key, 0);
+	ret = calc_root_size(root, &key, 0, unit_mode);
 	if (ret)
 		goto out;
 
 	pr_verbose(LOG_DEFAULT, "Calculating size of csum tree\n");
 	key.objectid = BTRFS_CSUM_TREE_OBJECTID;
-	ret = calc_root_size(root, &key, 0);
+	ret = calc_root_size(root, &key, 0, unit_mode);
 	if (ret)
 		goto out;
 
 	key.objectid = BTRFS_FS_TREE_OBJECTID;
 	key.offset = (u64)-1;
 	pr_verbose(LOG_DEFAULT, "Calculating size of fs tree\n");
-	ret = calc_root_size(root, &key, 1);
+	ret = calc_root_size(root, &key, 1, unit_mode);
 	if (ret)
 		goto out;
 out: