diff --git a/v1/internal/file/write.go b/v1/internal/file/write.go
new file mode 100644
index 0000000..0ee736f
--- /dev/null
+++ b/v1/internal/file/write.go
@@ -0,0 +1,79 @@
+package file
+
+import (
+	"encoding/json"
+	"fmt"
+	"os"
+	"strings"
+)
+
+// Supported extensions
+var extensions = [2]string{"txt", "json"}
+
+// Write to file
+func Write(path, domain, subdomain string, ips []string) error {
+	// Store extension
+	var extension string
+
+	// Split by extension
+	split := strings.Split(path, ".")
+
+	// No extension found
+	if len(split) != 2 {
+		extension = "txt"
+	} else {
+		extension = split[1]
+	}
+
+	// Open the file
+	file, err := os.OpenFile(path, os.O_APPEND|os.O_WRONLY|os.O_CREATE, 0600)
+	if err != nil {
+		return err
+	}
+	defer file.Close()
+
+	// Check extension
+	switch extension {
+	case "txt":
+		// Store IPs
+		ip := strings.Join(ips, ",")
+
+		// Format line
+		line := fmt.Sprintf("%s:%s:%s\n", domain, subdomain, ip)
+
+		// Write line
+		_, err := file.Write([]byte(line))
+		if err != nil {
+			return err
+		}
+
+	case "json":
+		// Format struct
+		output := struct {
+			Domain    string   `json:"domain"`
+			Subdomain string   `json:"subdomain"`
+			Hosts     []string `json:"hosts"`
+		}{
+			Domain:    domain,
+			Subdomain: subdomain,
+			Hosts:     ips,
+		}
+
+		// Marshal JSON
+		jason, err := json.Marshal(&output)
+		if err != nil {
+			return err
+		}
+
+		// Format line
+		line := string(jason) + "\n"
+
+		// Write line
+		_, err = file.Write([]byte(line))
+		if err != nil {
+			return err
+		}
+	}
+
+	return nil
+}