diff --git a/btrfs-snapshots.sh b/btrfs-snapshots.sh
index 92bd672..14ffb5d 100755
--- a/btrfs-snapshots.sh
+++ b/btrfs-snapshots.sh
@@ -1,10 +1,21 @@
 #!/bin/bash -e
 
+if test -e /etc/btrfs-snapshot.conf; then
+    . /etc/btrfs-snapshot.conf
+fi
+if test -e ~/.btrfs-snapshot; then
+    . ~/.btrfs-snapshot
+fi
+
+HOURLY_DEL=25
+DAILY_DEL=8
+WEEKLY_DEL=5
+MONTHLY_DEL=
 BTRFS_VOLUMES=${BTRFS_VOLUMES:-$(awk '!/^#/ && $3=="btrfs" {print $2}' /etc/fstab | tr '\n' ' ' | sed 's, $,,')}
 TMP_MNT=${TMP_MNT:-/var/tmp/btrfs-backup}
 
 vols=()
-del=
+del=${DEL}
 dryrun=0
 periodity=${0%/*}
 periodity=${periodity##*/}
@@ -14,10 +25,10 @@ else
     periodity=
 fi
 case "$periodity" in
-    (.hourly) del=25;;
-    (.daily) del=8;;
-    (.weekly) del=5;;
-    (.monthly);;
+    (.hourly) del=${HOURLY_DEL};;
+    (.daily) del=${DAILY_DEL};;
+    (.weekly) del=${WEEKLY_DEL};;
+    (.monthly) del=${MONTHLY_DEL};;
 esac
 while test $# -gt 0; do
     case "$1" in
diff --git a/install.sh b/install.sh
index 51fb569..62f9998 100755
--- a/install.sh
+++ b/install.sh
@@ -3,3 +3,11 @@
 for f in hourly daily weekly monthly; do
     sudo cp btrfs-snapshots.sh /etc/cron.$f/btrfs-snapshots;
 done
+if ! test -e /etc/btrfs-snapshots.conf; then
+    cat > /etc/btrfs-snapshots.conf <<EOF
+HOURLY_DEL=4
+DAILY_DEL=3
+WEEKLY_DEL=2
+MONTHLY_DEL=3
+EOF
+fi