diff --git a/main.go b/main.go
index d855906..6f9339f 100644
--- a/main.go
+++ b/main.go
@@ -6,6 +6,7 @@ import (
 	"os/exec"
 	"os/signal"
 	"strconv"
+	"strings"
 	"time"
 
 	"github.com/charmbracelet/bubbles/progress"
@@ -44,6 +45,7 @@ type model struct {
 	fullscreen    bool
 	width         int
 	height        int
+	err           error
 }
 
 func initialModel(fullscreen bool, colorLeft string, colorRight string) model {
@@ -53,14 +55,28 @@ func initialModel(fullscreen bool, colorLeft string, colorRight string) model {
 	for i := range inputs {
 		inputs[i] = textinput.New()
 		inputs[i].CharLimit = 10 // Increase char limit to allow duration strings
+
 		if i == 0 {
 			inputs[i].Focus() // Start focus on first input
 		}
 	}
 
+	validateDuration := func(text string) error {
+		_, err := parseDuration(text)
+		return err
+	}
+
+	validateInt := func(text string) error {
+		_, err := strconv.Atoi(text)
+		return fmt.Errorf("invalid int input: %w", err)
+	}
+
 	inputs[0].Placeholder = "Interval length (minutes or duration)"
+	inputs[0].Validate = validateDuration
 	inputs[1].Placeholder = "Break length (minutes or duration)"
+	inputs[1].Validate = validateDuration
 	inputs[2].Placeholder = "Number of intervals"
+	inputs[2].Validate = validateInt
 
 	return model{
 		inputs:        inputs,
@@ -79,6 +95,7 @@ func (m model) Init() tea.Cmd {
 	// Handle Ctrl+C for graceful exit
 	c := make(chan os.Signal, 1)
 	signal.Notify(c, os.Interrupt)
+
 	go func() {
 		<-c
 		fmt.Println("\nExiting...")
@@ -114,15 +131,22 @@ func (m model) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
 				if m.focusIndex == len(m.inputs)-1 {
 					focusTime, err := parseDuration(m.inputs[0].Value())
 					if err != nil {
-						focusTime, _ = time.ParseDuration(m.inputs[0].Value() + "m")
+						m.err = fmt.Errorf("error parsing focus time duration: %w", err)
+						return m, nil
 					}
 
 					breakTime, err := parseDuration(m.inputs[1].Value())
 					if err != nil {
-						breakTime, _ = time.ParseDuration(m.inputs[1].Value() + "m")
+						m.err = fmt.Errorf("error parsing break time duration: %w", err)
+						return m, nil
+					}
+
+					m.intervals, err = strconv.Atoi(m.inputs[2].Value())
+					if err != nil {
+						m.err = fmt.Errorf("error parsing interval: %w", err)
+						return m, nil
 					}
 
-					m.intervals = atoi(m.inputs[2].Value())
 					m.focusTime = focusTime
 					m.breakTime = breakTime
 					m.remaining = focusTime
@@ -203,24 +227,41 @@ func tick() tea.Cmd {
 
 // View rendering for input and timer screens
 func (m model) View() string {
+	var s strings.Builder
+
 	switch m.currentScreen {
 	case inputScreen:
-		return m.inputScreenView()
+		s.WriteString(m.inputScreenView())
 	case timerScreen:
-		return m.timerScreenView()
+		s.WriteString(m.timerScreenView())
 	}
-	return ""
+
+	if m.err != nil {
+		s.WriteString(fmt.Sprintf("\n\nError: %v", m.err))
+	}
+
+	return s.String()
 }
 
 // View for input screen
 func (m model) inputScreenView() string {
-	var builder string
-	builder = "Enter your Pomodoro settings:\n\n"
+	var builder strings.Builder
+
+	builder.WriteString("Enter your Pomodoro settings:\n\n")
+
 	for i := range m.inputs {
-		builder += m.inputs[i].View() + "\n"
+		builder.WriteString(m.inputs[i].View())
+
+		if m.inputs[i].Value() != "" && m.inputs[i].Err != nil {
+			builder.WriteString(fmt.Sprintf("Error: %v", m.inputs[i].Err))
+		}
+
+		builder.WriteString("\n")
 	}
-	builder += "\nUse TAB to navigate, ENTER to start."
-	return builder
+
+	builder.WriteString("\nUse TAB to navigate, ENTER to start.")
+
+	return builder.String()
 }
 
 // View for timer screen with optional fullscreen centering
@@ -236,6 +277,7 @@ func (m model) timerScreenView() string {
 	if m.fullscreen {
 		return lipgloss.NewStyle().Width(m.width).Height(m.height).Align(lipgloss.Center, lipgloss.Center).Render(timerView)
 	}
+
 	return timerView
 }
 
@@ -256,6 +298,7 @@ func (m *model) runCommands(commands []string) {
 		cmd := exec.Command("sh", "-c", cmdStr)
 		cmd.Stdout = os.Stdout
 		cmd.Stderr = os.Stderr
+
 		if err := cmd.Run(); err != nil {
 			fmt.Printf("Error running command: %v\n", err)
 		}
@@ -267,13 +310,13 @@ func parseDuration(input string) (time.Duration, error) {
 	if minutes, err := strconv.Atoi(input); err == nil {
 		return time.Duration(minutes) * time.Minute, nil
 	}
-	return time.ParseDuration(input)
-}
 
-// Helper to convert string to int
-func atoi(s string) int {
-	n, _ := strconv.Atoi(s)
-	return n
+	d, err := time.ParseDuration(input)
+	if err != nil {
+		return d, fmt.Errorf("error parsing duration: %w", err)
+	}
+
+	return d, nil
 }
 
 func main() {
@@ -299,26 +342,29 @@ func main() {
 				Usage: "Enable fullscreen mode",
 			},
 			&cli.DurationFlag{
-				Name:  "focus",
-				Usage: "Focus time duration (default prompt for input)",
+				Name:        "focus",
+				Usage:       "Focus time duration",
+				DefaultText: "prompt for input",
 			},
 			&cli.DurationFlag{
-				Name:  "break",
-				Usage: "Break time duration (default prompt for input)",
+				Name:        "break",
+				Usage:       "Break time duration",
+				DefaultText: "prompt for input",
 			},
 			&cli.IntFlag{
-				Name:  "intervals",
-				Usage: "Number of intervals (default prompt for input)",
+				Name:        "intervals",
+				Usage:       "Number of intervals",
+				DefaultText: "prompt for input",
 			},
 			&cli.StringFlag{
-				Name:        "color-left",
-				Usage:       "Left color for progress bar",
-				DefaultText: "#ffdd57",
+				Name:  "color-left",
+				Usage: "Left color for progress bar",
+				Value: "#ffdd57",
 			},
 			&cli.StringFlag{
-				Name:        "color-right",
-				Usage:       "Right color for progress bar",
-				DefaultText: "#57ddff",
+				Name:  "color-right",
+				Usage: "Right color for progress bar",
+				Value: "#57ddff",
 			},
 			&cli.BoolFlag{
 				Name:  "version",
@@ -352,6 +398,7 @@ func main() {
 			// Start tea program
 			p := tea.NewProgram(m, tea.WithAltScreen())
 			_, err := p.Run()
+
 			return err
 		},
 	}