diff --git a/cmd/promtool/main.go b/cmd/promtool/main.go
index 5cc82a0a6..56c99b689 100644
--- a/cmd/promtool/main.go
+++ b/cmd/promtool/main.go
@@ -18,6 +18,7 @@ import (
 	"fmt"
 	"io/ioutil"
 	"math"
+	"net/url"
 	"os"
 	"path/filepath"
 	"strconv"