diff --git a/entry.go b/entry.go
index e343a27..863e89d 100644
--- a/entry.go
+++ b/entry.go
@@ -129,67 +129,79 @@ func (entry *Entry) Panic(args ...interface{}) {
 // Entry Printf family functions
 
 func (entry *Entry) Debugf(format string, args ...interface{}) {
-	entry.Debug(fmt.Sprintf(format, args...))
+	if entry.logger.Level >= Debug {
+		entry.Debug(fmt.Sprintf(format, args...))
+	}
 }
 
 func (entry *Entry) Infof(format string, args ...interface{}) {
-	entry.Info(fmt.Sprintf(format, args...))
+	if entry.logger.Level >= Info {
+		entry.Info(fmt.Sprintf(format, args...))
+	}
 }
 
 func (entry *Entry) Printf(format string, args ...interface{}) {
-	entry.Info(fmt.Sprintf(format, args...))
+	entry.Info(format, args...)
 }
 
 func (entry *Entry) Warnf(format string, args ...interface{}) {
-	entry.Warn(fmt.Sprintf(format, args...))
+	if entry.logger.Level >= Warn {
+		entry.Warn(fmt.Sprintf(format, args...))
+	}
 }
 
 func (entry *Entry) Warningf(format string, args ...interface{}) {
-	entry.Warn(fmt.Sprintf(format, args...))
+	entry.Warnf(format, args...)
 }
 
 func (entry *Entry) Errorf(format string, args ...interface{}) {
-	entry.Error(fmt.Sprintf(format, args...))
+	if entry.logger.Level >= Error {
+		entry.Error(fmt.Sprintf(format, args...))
+	}
 }
 
 func (entry *Entry) Fatalf(format string, args ...interface{}) {
-	entry.Fatal(fmt.Sprintf(format, args...))
+	if entry.logger.Level >= Fatal {
+		entry.Fatal(fmt.Sprintf(format, args...))
+	}
 }
 
 func (entry *Entry) Panicf(format string, args ...interface{}) {
-	entry.Panic(fmt.Sprintf(format, args...))
+	if entry.logger.Level >= Panic {
+		entry.Panic(fmt.Sprintf(format, args...))
+	}
 }
 
 // Entry Println family functions
 
 func (entry *Entry) Debugln(args ...interface{}) {
-	entry.Debug(fmt.Sprint(args...))
+	entry.Debug(args...)
 }
 
 func (entry *Entry) Infoln(args ...interface{}) {
-	entry.Info(fmt.Sprint(args...))
+	entry.Info(args...)
 }
 
 func (entry *Entry) Println(args ...interface{}) {
-	entry.Info(fmt.Sprint(args...))
+	entry.Info(args...)
 }
 
 func (entry *Entry) Warnln(args ...interface{}) {
-	entry.Warn(fmt.Sprint(args...))
+	entry.Warn(args...)
 }
 
 func (entry *Entry) Warningln(args ...interface{}) {
-	entry.Warn(fmt.Sprint(args...))
+	entry.Warn(args...)
 }
 
 func (entry *Entry) Errorln(args ...interface{}) {
-	entry.Error(fmt.Sprint(args...))
+	entry.Error(args...)
 }
 
 func (entry *Entry) Fatalln(args ...interface{}) {
-	entry.Fatal(fmt.Sprint(args...))
+	entry.Fatal(args...)
 }
 
 func (entry *Entry) Panicln(args ...interface{}) {
-	entry.Panic(fmt.Sprint(args...))
+	entry.Panic(args...)
 }
diff --git a/logrus_test.go b/logrus_test.go
index 64baa40..5889db5 100644
--- a/logrus_test.go
+++ b/logrus_test.go
@@ -3,7 +3,9 @@ package logrus
 import (
 	"bytes"
 	"encoding/json"
+	"io/ioutil"
 	"testing"
+	"time"
 
 	"github.com/stretchr/testify/assert"
 )
@@ -50,3 +52,59 @@ func TestWarn(t *testing.T) {
 		assert.Equal(t, fields["level"], "warning")
 	})
 }
+
+type SlowString string
+
+func (s SlowString) String() string {
+	time.Sleep(time.Millisecond)
+	return string(s)
+}
+
+func getLogAtLevel(l Level) *Logger {
+	log := New()
+	log.Level = l
+	log.Out = ioutil.Discard
+	return log
+}
+
+func BenchmarkLevelDisplayed(b *testing.B) {
+	log := getLogAtLevel(Info)
+	for i := 0; i < b.N; i++ {
+		log.Info(SlowString("foo"))
+	}
+}
+
+func BenchmarkLevelHidden(b *testing.B) {
+	log := getLogAtLevel(Info)
+	for i := 0; i < b.N; i++ {
+		log.Debug(SlowString("foo"))
+	}
+}
+
+func BenchmarkLevelfDisplayed(b *testing.B) {
+	log := getLogAtLevel(Info)
+	for i := 0; i < b.N; i++ {
+		log.Infof("%s", SlowString("foo"))
+	}
+}
+
+func BenchmarkLevelfHidden(b *testing.B) {
+	log := getLogAtLevel(Info)
+	for i := 0; i < b.N; i++ {
+		log.Debugf("%s", SlowString("foo"))
+	}
+}
+
+func BenchmarkLevellnDisplayed(b *testing.B) {
+	log := getLogAtLevel(Info)
+	for i := 0; i < b.N; i++ {
+		log.Infoln(SlowString("foo"))
+	}
+}
+
+func BenchmarkLevellnHidden(b *testing.B) {
+	log := getLogAtLevel(Info)
+	for i := 0; i < b.N; i++ {
+		log.Debugln(SlowString("foo"))
+	}
+}