diff --git a/internal/misc/hex.go b/internal/misc/hex.go
new file mode 100644
index 0000000..2a637c0
--- /dev/null
+++ b/internal/misc/hex.go
@@ -0,0 +1,62 @@
+package misc
+
+import (
+	"encoding/hex"
+	"fmt"
+
+	"bandr.me/p/pocryp/internal/cli/cmd"
+	"bandr.me/p/pocryp/internal/util/stdfile"
+)
+
+var HexCmd = &cmd.Command{
+	Name:  "hex",
+	Run:   runHex,
+	Brief: "Hex encode or decode",
+
+	Usage: `Usage: pocryp hex [-in INPUT] [-out OUTPUT]
+
+Hex encode or decode(if -d is specified) input to output.
+
+If -in is not specified, stdin will be read.
+If -out is not specified, the output will be printed to stdout.
+`,
+}
+
+func runHex(cmd *cmd.Command) error {
+	fOutput := cmd.Flags.String("out", "", "Write the result to the file at path OUTPUT.")
+	fInput := cmd.Flags.String("in", "", "Read data from the file at path INPUT.")
+	fDecode := cmd.Flags.Bool("d", false, "Decode data.")
+
+	if isHelp, err := cmd.Parse(); err != nil {
+		if isHelp {
+			return nil
+		}
+		return err
+	}
+
+	sf, err := stdfile.New(*fInput, *fOutput)
+	if err != nil {
+		return err
+	}
+	defer sf.Close()
+
+	input, err := sf.Read()
+	if err != nil {
+		return err
+	}
+
+	var output string
+	if *fDecode {
+		b, err := hex.DecodeString(string(input))
+		if err != nil {
+			return fmt.Errorf("failed to decode input: %w", err)
+		}
+		output = string(b)
+	} else {
+		output = hex.EncodeToString(input)
+	}
+
+	fmt.Fprint(sf.Out, output)
+
+	return nil
+}
diff --git a/main.go b/main.go
index e812a38..1569310 100644
--- a/main.go
+++ b/main.go
@@ -88,6 +88,7 @@ func main() {
 	a.Add(
 		"Miscellaneous",
 		misc.Base64Cmd,
+		misc.HexCmd,
 	)
 
 	if err := a.Run(os.Args[1:]...); err != nil {