diff --git a/example/jsonmarshal/main.go b/example/jsonmarshal/main.go
new file mode 100644
index 0000000..23d7cc8
--- /dev/null
+++ b/example/jsonmarshal/main.go
@@ -0,0 +1,32 @@
+package main
+
+import (
+	"fmt"
+
+	"github.com/linhbkhn95/int256"
+)
+
+type PoolState struct {
+	Price *int256.Int
+	Tick  int64
+}
+
+func main() {
+	state1 := &PoolState{
+		Price: fromString("100000000000000000000000"),
+		Tick:  1000,
+	}
+	state2 := &PoolState{
+		Price: fromString("-100000000000000000000000"),
+		Tick:  1000,
+	}
+
+	fmt.Println("state1", state1)
+	fmt.Println("state2", state2)
+
+}
+
+func fromString(str string) *int256.Int {
+	i, _ := new(int256.Int).SetString(str)
+	return i
+}