diff --git a/cmd/genautocomplete/genautocomplete_bash.go b/cmd/genautocomplete/genautocomplete_bash.go
index 63660e283..f371d690c 100644
--- a/cmd/genautocomplete/genautocomplete_bash.go
+++ b/cmd/genautocomplete/genautocomplete_bash.go
@@ -2,6 +2,7 @@ package genautocomplete
 
 import (
 	"log"
+	"os"
 
 	"github.com/rclone/rclone/cmd"
 	"github.com/spf13/cobra"
@@ -29,11 +30,20 @@ them directly
 
 If you supply a command line argument the script will be written
 there.
+
+If output_file is "-", then the output will be written to stdout.
 `,
 	Run: func(command *cobra.Command, args []string) {
 		cmd.CheckArgs(0, 1, command, args)
 		out := "/etc/bash_completion.d/rclone"
 		if len(args) > 0 {
+			if args[0] == "-" {
+				err := cmd.Root.GenBashCompletion(os.Stdout)
+				if err != nil {
+					log.Fatal(err)
+				}
+				return
+			}
 			out = args[0]
 		}
 		err := cmd.Root.GenBashCompletionFile(out)
diff --git a/cmd/genautocomplete/genautocomplete_fish.go b/cmd/genautocomplete/genautocomplete_fish.go
index edb327b8b..a60230c40 100644
--- a/cmd/genautocomplete/genautocomplete_fish.go
+++ b/cmd/genautocomplete/genautocomplete_fish.go
@@ -2,6 +2,7 @@ package genautocomplete
 
 import (
 	"log"
+	"os"
 
 	"github.com/rclone/rclone/cmd"
 	"github.com/spf13/cobra"
@@ -29,11 +30,20 @@ them directly
 
 If you supply a command line argument the script will be written
 there.
+
+If output_file is "-", then the output will be written to stdout.
 `,
 	Run: func(command *cobra.Command, args []string) {
 		cmd.CheckArgs(0, 1, command, args)
 		out := "/etc/fish/completions/rclone.fish"
 		if len(args) > 0 {
+			if args[0] == "-" {
+				err := cmd.Root.GenFishCompletion(os.Stdout, true)
+				if err != nil {
+					log.Fatal(err)
+				}
+				return
+			}
 			out = args[0]
 		}
 		err := cmd.Root.GenFishCompletionFile(out, true)
diff --git a/cmd/genautocomplete/genautocomplete_test.go b/cmd/genautocomplete/genautocomplete_test.go
index e97ad1169..ce766c6fd 100644
--- a/cmd/genautocomplete/genautocomplete_test.go
+++ b/cmd/genautocomplete/genautocomplete_test.go
@@ -11,8 +11,10 @@ import (
 func TestCompletionBash(t *testing.T) {
 	tempFile, err := ioutil.TempFile("", "completion_bash")
 	assert.NoError(t, err)
-	defer func() { _ = tempFile.Close() }()
-	defer func() { _ = os.Remove(tempFile.Name()) }()
+	defer func() {
+		_ = tempFile.Close()
+		_ = os.Remove(tempFile.Name())
+	}()
 
 	bashCommandDefinition.Run(bashCommandDefinition, []string{tempFile.Name()})
 
@@ -21,11 +23,32 @@ func TestCompletionBash(t *testing.T) {
 	assert.NotEmpty(t, string(bs))
 }
 
+func TestCompletionBashStdout(t *testing.T) {
+	originalStdout := os.Stdout
+	tempFile, err := ioutil.TempFile("", "completion_zsh")
+	assert.NoError(t, err)
+	defer func() {
+		_ = tempFile.Close()
+		_ = os.Remove(tempFile.Name())
+	}()
+
+	os.Stdout = tempFile
+	defer func() { os.Stdout = originalStdout }()
+
+	bashCommandDefinition.Run(bashCommandDefinition, []string{"-"})
+
+	output, err := ioutil.ReadFile(tempFile.Name())
+	assert.NoError(t, err)
+	assert.NotEmpty(t, string(output))
+}
+
 func TestCompletionZsh(t *testing.T) {
 	tempFile, err := ioutil.TempFile("", "completion_zsh")
 	assert.NoError(t, err)
-	defer func() { _ = tempFile.Close() }()
-	defer func() { _ = os.Remove(tempFile.Name()) }()
+	defer func() {
+		_ = tempFile.Close()
+		_ = os.Remove(tempFile.Name())
+	}()
 
 	zshCommandDefinition.Run(zshCommandDefinition, []string{tempFile.Name()})
 
@@ -34,11 +57,31 @@ func TestCompletionZsh(t *testing.T) {
 	assert.NotEmpty(t, string(bs))
 }
 
+func TestCompletionZshStdout(t *testing.T) {
+	originalStdout := os.Stdout
+	tempFile, err := ioutil.TempFile("", "completion_zsh")
+	assert.NoError(t, err)
+	defer func() {
+		_ = tempFile.Close()
+		_ = os.Remove(tempFile.Name())
+	}()
+
+	os.Stdout = tempFile
+	defer func() { os.Stdout = originalStdout }()
+
+	zshCommandDefinition.Run(zshCommandDefinition, []string{"-"})
+	output, err := ioutil.ReadFile(tempFile.Name())
+	assert.NoError(t, err)
+	assert.NotEmpty(t, string(output))
+}
+
 func TestCompletionFish(t *testing.T) {
 	tempFile, err := ioutil.TempFile("", "completion_fish")
 	assert.NoError(t, err)
-	defer func() { _ = tempFile.Close() }()
-	defer func() { _ = os.Remove(tempFile.Name()) }()
+	defer func() {
+		_ = tempFile.Close()
+		_ = os.Remove(tempFile.Name())
+	}()
 
 	fishCommandDefinition.Run(fishCommandDefinition, []string{tempFile.Name()})
 
@@ -46,3 +89,22 @@ func TestCompletionFish(t *testing.T) {
 	assert.NoError(t, err)
 	assert.NotEmpty(t, string(bs))
 }
+
+func TestCompletionFishStdout(t *testing.T) {
+	originalStdout := os.Stdout
+	tempFile, err := ioutil.TempFile("", "completion_zsh")
+	assert.NoError(t, err)
+	defer func() {
+		_ = tempFile.Close()
+		_ = os.Remove(tempFile.Name())
+	}()
+
+	os.Stdout = tempFile
+	defer func() { os.Stdout = originalStdout }()
+
+	fishCommandDefinition.Run(fishCommandDefinition, []string{"-"})
+
+	output, err := ioutil.ReadFile(tempFile.Name())
+	assert.NoError(t, err)
+	assert.NotEmpty(t, string(output))
+}
diff --git a/cmd/genautocomplete/genautocomplete_zsh.go b/cmd/genautocomplete/genautocomplete_zsh.go
index 0d635506d..6a2c1c4a0 100644
--- a/cmd/genautocomplete/genautocomplete_zsh.go
+++ b/cmd/genautocomplete/genautocomplete_zsh.go
@@ -30,11 +30,20 @@ them directly
 
 If you supply a command line argument the script will be written
 there.
+
+If output_file is "-", then the output will be written to stdout.
 `,
 	Run: func(command *cobra.Command, args []string) {
 		cmd.CheckArgs(0, 1, command, args)
 		out := "/usr/share/zsh/vendor-completions/_rclone"
 		if len(args) > 0 {
+			if args[0] == "-" {
+				err := cmd.Root.GenZshCompletion(os.Stdout)
+				if err != nil {
+					log.Fatal(err)
+				}
+				return
+			}
 			out = args[0]
 		}
 		outFile, err := os.Create(out)
diff --git a/docs/content/commands/rclone_genautocomplete_bash.md b/docs/content/commands/rclone_genautocomplete_bash.md
index 72dc7cc21..27928c680 100644
--- a/docs/content/commands/rclone_genautocomplete_bash.md
+++ b/docs/content/commands/rclone_genautocomplete_bash.md
@@ -27,6 +27,7 @@ them directly
 If you supply a command line argument the script will be written
 there.
 
+If output_file is `-`, then the output will be written to stdout.
 
 ```
 rclone genautocomplete bash [output_file] [flags]
diff --git a/docs/content/commands/rclone_genautocomplete_fish.md b/docs/content/commands/rclone_genautocomplete_fish.md
index 8d9a122ed..d9ba9706c 100644
--- a/docs/content/commands/rclone_genautocomplete_fish.md
+++ b/docs/content/commands/rclone_genautocomplete_fish.md
@@ -27,6 +27,7 @@ them directly
 If you supply a command line argument the script will be written
 there.
 
+If output_file is `-`, then the output will be written to stdout.
 
 ```
 rclone genautocomplete fish [output_file] [flags]
diff --git a/docs/content/commands/rclone_genautocomplete_zsh.md b/docs/content/commands/rclone_genautocomplete_zsh.md
index 6816f7dde..e31df0726 100644
--- a/docs/content/commands/rclone_genautocomplete_zsh.md
+++ b/docs/content/commands/rclone_genautocomplete_zsh.md
@@ -27,6 +27,7 @@ them directly
 If you supply a command line argument the script will be written
 there.
 
+If output_file is `-`, then the output will be written to stdout.
 
 ```
 rclone genautocomplete zsh [output_file] [flags]
diff --git a/go.sum b/go.sum
index 4b5ec2d63..e5abaa4a5 100644
--- a/go.sum
+++ b/go.sum
@@ -400,6 +400,7 @@ github.com/spf13/pflag v1.0.5 h1:iy+VFUOCP1a+8yFto/drg2CJ5u0yRoB7fZw3DKv/JXA=
 github.com/spf13/pflag v1.0.5/go.mod h1:McXfInJRrz4CZXVZOBLb0bTZqETkiAhM9Iw0y3An2Bg=
 github.com/spf13/viper v1.4.0/go.mod h1:PTJ7Z/lr49W6bUbkmS1V3by4uWynFiR9p7+dSq/yZzE=
 github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
+github.com/stretchr/objx v0.1.1 h1:2vfRuCMp5sSVIDSqO8oNnWJq7mPa6KVP3iPIwFBuy8A=
 github.com/stretchr/objx v0.1.1/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
 github.com/stretchr/testify v1.2.1/go.mod h1:a8OnRcib4nhh0OaRAV+Yts87kKdq0PP7pXfy6kDkUVs=
 github.com/stretchr/testify v1.2.2/go.mod h1:a8OnRcib4nhh0OaRAV+Yts87kKdq0PP7pXfy6kDkUVs=