diff --git a/du.1 b/du.1
index 932e693..3320c8b 100644
--- a/du.1
+++ b/du.1
@@ -19,3 +19,7 @@ Display an entry for each file in the file hierarchy.
 .TP
 .BI \-s
 Display only the grand total for the specified files.
+.TP
+.BI \-k
+By default all sizes are reported in 512-byte block counts.
+The -k option causes the numbers to be reported in kilobyte counts.
diff --git a/du.c b/du.c
index 3c6461b..4b3ebb0 100644
--- a/du.c
+++ b/du.c
@@ -15,6 +15,7 @@ static long blksize = 512;
 
 static bool aflag = false;
 static bool sflag = false;
+static bool kflag = false;
 
 static long du(const char *);
 static void print(long n, char *path);
@@ -38,6 +39,9 @@ main(int argc, char *argv[])
 	case 's':
 		sflag = true;
 		break;
+	case 'k':
+		kflag = true;
+		break;
 	default:
 		usage();
 	} ARGEND;
@@ -46,6 +50,9 @@ main(int argc, char *argv[])
 	if (bsize)
 		blksize = estrtol(bsize, 0);
 
+	if (kflag)
+		blksize = 1024;
+
 	if (argc < 1) {
 		n = du(".");
 		if (sflag)