diff --git a/page.go b/page.go
index db48c59..95aa946 100644
--- a/page.go
+++ b/page.go
@@ -184,7 +184,8 @@ func (p *Page) startSimulation() error {
 	}()
 
 	backend := p.simulationWidget.Address()
-	sim, err := p.runSimulation(backend)
+	ttl := p.simulationWidget.TTL()
+	sim, err := p.runSimulation(backend, ttl)
 	if err != nil {
 		return err
 	}
diff --git a/simulation.go b/simulation.go
index a9967cd..259a55d 100644
--- a/simulation.go
+++ b/simulation.go
@@ -28,8 +28,8 @@ type SimulationRequest struct {
 
 // runSimulation starts whisper message propagation simulation,
 // remotely talking to simulation backend with given address.
-func (p *Page) runSimulation(address string) (*Simulation, error) {
-	buf, err := p.newPOSTSimulationRequest()
+func (p *Page) runSimulation(address string, ttl int) (*Simulation, error) {
+	buf, err := p.newPOSTSimulationRequest(ttl)
 	if err != nil {
 		return nil, fmt.Errorf("Internal error. See console output.")
 	}
@@ -53,10 +53,10 @@ func (p *Page) runSimulation(address string) (*Simulation, error) {
 
 // newPOSTSimulationRequest generates SimulationReqeust and
 // prepares it as io.Reader for usage with http.Post.
-func (p *Page) newPOSTSimulationRequest() (io.Reader, error) {
+func (p *Page) newPOSTSimulationRequest(ttl int) (io.Reader, error) {
 	req := SimulationRequest{
 		SenderIdx: 0,
-		TTL:       10,
+		TTL:       ttl,
 		MsgSize:   400,
 		Network:   p.currentNetworkJSON(),
 	}
diff --git a/widgets/simulation.go b/widgets/simulation.go
index 615de18..604d574 100644
--- a/widgets/simulation.go
+++ b/widgets/simulation.go
@@ -1,6 +1,8 @@
 package widgets
 
 import (
+	"fmt"
+
 	"github.com/gopherjs/vecty"
 	"github.com/gopherjs/vecty/elem"
 	"github.com/gopherjs/vecty/event"
@@ -53,8 +55,19 @@ func (s *Simulation) Render() vecty.ComponentOrHTML {
 						),
 						vecty.Class("input", "is-small"),
 						prop.Value(s.address),
-						vecty.Attribute("placehoder", "backend url"),
-						event.Input(s.onEditInput),
+						event.Input(s.onAddressChange),
+					),
+				),
+			),
+			InputField("TTL:", "Message time to live value (in seconds)",
+				elem.Input(
+					vecty.Markup(
+						vecty.MarkupIf(s.inProgress,
+							vecty.Attribute("disabled", "true"),
+						),
+						vecty.Class("input", "is-small"),
+						prop.Value(fmt.Sprint(s.ttl)),
+						event.Input(s.onTTLChange),
 					),
 				),
 			),
@@ -99,17 +112,28 @@ func (s *Simulation) Render() vecty.ComponentOrHTML {
 	)
 }
 
-func (s *Simulation) onEditInput(event *vecty.Event) {
+func (s *Simulation) onAddressChange(event *vecty.Event) {
 	value := event.Target.Get("value").String()
 
 	s.address = value
 }
 
+func (s *Simulation) onTTLChange(event *vecty.Event) {
+	value := event.Target.Get("value").Int()
+
+	s.ttl = value
+}
+
 // Address returns the current backend address.
 func (s *Simulation) Address() string {
 	return s.address
 }
 
+// TTL returns the current TTL value.
+func (s *Simulation) TTL() int {
+	return s.ttl
+}
+
 func (s *Simulation) onSimulateClick(e *vecty.Event) {
 	go func() {
 		s.errMsg = ""