diff --git a/cmd/rekor-server/app/root.go b/cmd/rekor-server/app/root.go
index 4d60922e9..954e451c3 100644
--- a/cmd/rekor-server/app/root.go
+++ b/cmd/rekor-server/app/root.go
@@ -64,7 +64,7 @@ func init() {
 	rootCmd.PersistentFlags().String("trillian_log_server.address", "127.0.0.1", "Trillian log server address")
 	rootCmd.PersistentFlags().Uint16("trillian_log_server.port", 8090, "Trillian log server port")
 	rootCmd.PersistentFlags().Uint("trillian_log_server.tlog_id", 0, "Trillian tree id")
-	rootCmd.PersistentFlags().String("trillian_log_server.sharding_config", "", "path to config file for inactive shards")
+	rootCmd.PersistentFlags().String("trillian_log_server.sharding_config", "", "path to config file for inactive shards, in JSON or YAML")
 
 	hostname, err := os.Hostname()
 	if err != nil {
diff --git a/pkg/sharding/ranges.go b/pkg/sharding/ranges.go
index 5b2772251..70485ec5d 100644
--- a/pkg/sharding/ranges.go
+++ b/pkg/sharding/ranges.go
@@ -18,6 +18,7 @@ package sharding
 import (
 	"context"
 	"encoding/base64"
+	"encoding/json"
 	"errors"
 	"fmt"
 	"io/ioutil"
@@ -82,6 +83,10 @@ func logRangesFromPath(path string) (Ranges, error) {
 		return Ranges{}, nil
 	}
 	if err := yaml.Unmarshal(contents, &ranges); err != nil {
+		// Try to use JSON
+		if jerr := json.Unmarshal(contents, &ranges); jerr == nil {
+			return ranges, nil
+		}
 		return Ranges{}, err
 	}
 	return ranges, nil
diff --git a/pkg/sharding/ranges_test.go b/pkg/sharding/ranges_test.go
index 6e560bc4e..ae9d1123b 100644
--- a/pkg/sharding/ranges_test.go
+++ b/pkg/sharding/ranges_test.go
@@ -96,6 +96,32 @@ func TestLogRangesFromPath(t *testing.T) {
 	}
 }
 
+func TestLogRangesFromPathJSON(t *testing.T) {
+	contents := `[{"treeID": 0001, "treeLength": 3, "encodedPublicKey":"c2hhcmRpbmcK"}, {"treeID": 0002, "treeLength": 4}]`
+	file := filepath.Join(t.TempDir(), "sharding-config")
+	if err := ioutil.WriteFile(file, []byte(contents), 0644); err != nil {
+		t.Fatal(err)
+	}
+	expected := Ranges{
+		{
+			TreeID:           1,
+			TreeLength:       3,
+			EncodedPublicKey: "c2hhcmRpbmcK",
+		}, {
+			TreeID:     2,
+			TreeLength: 4,
+		},
+	}
+
+	got, err := logRangesFromPath(file)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if !reflect.DeepEqual(expected, got) {
+		t.Fatalf("expected %v got %v", expected, got)
+	}
+}
+
 func TestLogRanges_ResolveVirtualIndex(t *testing.T) {
 	lrs := LogRanges{
 		inactive: []LogRange{