diff --git a/config_example.toml b/config_example.toml
index 8f19ba4..48ad64b 100644
--- a/config_example.toml
+++ b/config_example.toml
@@ -20,6 +20,9 @@ state_path     = "/var/lib/collector/state.json"
 # Export nodes and graph periodically
 save_interval = "5s"
 
+# Set node to offline if not seen within this period
+offline_after = "10m"
+
 # Prune offline nodes after a time of inactivity
 prune_after = "7d"
 
diff --git a/models/config.go b/models/config.go
index e2d4295..bdb62a7 100644
--- a/models/config.go
+++ b/models/config.go
@@ -25,6 +25,7 @@ type Config struct {
 		GraphPath    string
 		StatePath    string
 		SaveInterval Duration // Save nodes periodically
+		OfflineAfter Duration // Set node to offline if not seen within this period
 		PruneAfter   Duration // Remove nodes after n days of inactivity
 	}
 	Influxdb struct {
diff --git a/models/nodes.go b/models/nodes.go
index fa43be9..0a504bf 100644
--- a/models/nodes.go
+++ b/models/nodes.go
@@ -146,25 +146,25 @@ func (nodes *Nodes) worker() {
 func (nodes *Nodes) expire() {
 	now := jsontime.Now()
 
-	// Nodes last seen before expireTime will be removed
-	pruneAfter := nodes.config.Nodes.PruneAfter.Duration
-	if pruneAfter == 0 {
-		pruneAfter = time.Hour * 24 * 7 // our default
+	// Nodes last seen before expireAfter will be removed
+	prunePeriod := nodes.config.Nodes.PruneAfter.Duration
+	if prunePeriod == 0 {
+		prunePeriod = time.Hour * 24 * 7 // our default
 	}
-	expireTime := now.Add(-pruneAfter)
+	pruneAfter := now.Add(-prunePeriod)
 
-	// Nodes last seen before offlineTime are changed to 'offline'
-	offlineTime := now.Add(-time.Minute * 10)
+	// Nodes last seen within OfflineAfter are changed to 'offline'
+	offlineAfter := now.Add(-nodes.config.Nodes.OfflineAfter.Duration)
 
 	// Locking foo
 	nodes.Lock()
 	defer nodes.Unlock()
 
 	for id, node := range nodes.List {
-		if node.Lastseen.Before(expireTime) {
+		if node.Lastseen.Before(pruneAfter) {
 			// expire
 			delete(nodes.List, id)
-		} else if node.Lastseen.Before(offlineTime) {
+		} else if node.Lastseen.Before(offlineAfter) {
 			// set to offline
 			node.Flags.Online = false
 		}
diff --git a/models/nodes_test.go b/models/nodes_test.go
index aa84adb..d1d9694 100644
--- a/models/nodes_test.go
+++ b/models/nodes_test.go
@@ -13,6 +13,7 @@ import (
 func TestExpire(t *testing.T) {
 	assert := assert.New(t)
 	config := &Config{}
+	config.Nodes.OfflineAfter.Duration = time.Minute * 10
 	config.Nodes.PruneAfter.Duration = time.Hour * 24 * 6
 	nodes := &Nodes{
 		config: config,