diff --git a/tools/sha1 b/tools/sha1
index f76787c59fb47..4224a7138b037 100755
--- a/tools/sha1
+++ b/tools/sha1
@@ -7,9 +7,9 @@ set -o pipefail
 in=$1
 out=$2
 
-if ( which sha1sum > /dev/null ); then
+if ( command -v sha1sum > /dev/null ); then
   (sha1sum $in | cut -d' ' -f1) > $out
-elif ( which shasum > /dev/null ); then
+elif ( command -v shasum > /dev/null ); then
   (shasum -a 1 $in | cut -d' ' -f1) > $out
 else
   echo "Neither sha1sum nor shasum command is available"
diff --git a/tools/sha256 b/tools/sha256
index c05a132cbdf75..1dae065dd9a07 100755
--- a/tools/sha256
+++ b/tools/sha256
@@ -7,9 +7,9 @@ set -o pipefail
 in=$1
 out=$2
 
-if ( which sha256sum > /dev/null ); then
+if ( command -v sha256sum > /dev/null ); then
   (sha256sum $in | cut -d' ' -f1) > $out
-elif ( which shasum > /dev/null ); then
+elif ( command -v shasum > /dev/null ); then
   (shasum -a 256 $in | cut -d' ' -f1) > $out
 else
   echo "Neither sha256sum nor shasum command is available"