diff --git a/ron.go b/ron.go
index e6be920..dc88158 100644
--- a/ron.go
+++ b/ron.go
@@ -20,7 +20,7 @@ type Engine struct {
 	Renderer *Render
 }
 
-func (c *Context) JSON(code int, data Data) {
+func (c *Context) JSON(code int, data any) {
 	c.W.WriteHeader(code)
 	c.W.Header().Set("Content-Type", "application/json")
 	encoder := json.NewEncoder(c.W)
@@ -31,9 +31,13 @@ func (c *Context) JSON(code int, data Data) {
 
 func (c *Context) HTML(code int, name string, data Data) {
 	c.W.WriteHeader(code)
-	c.E.Renderer.Template(c.W, name, &TemplateData{
+	c.W.Header().Set("Content-Type", "text/html; charset=utf-8")
+	err := c.E.Renderer.Template(c.W, name, &TemplateData{
 		Data: data,
 	})
+	if err != nil {
+		http.Error(c.W, err.Error(), http.StatusInternalServerError)
+	}
 }
 
 func New() *Engine {
diff --git a/ron_test.go b/ron_test.go
new file mode 100644
index 0000000..6adc7ab
--- /dev/null
+++ b/ron_test.go
@@ -0,0 +1,76 @@
+package ron
+
+import (
+	"net/http"
+	"net/http/httptest"
+	"os"
+	"testing"
+)
+
+type Foo struct {
+	Bar string  `json:"bar"`
+	Taz int     `json:"taz"`
+	Car *string `json:"car"`
+}
+
+func Test_JSON(t *testing.T) {
+	rr := httptest.NewRecorder()
+	c := &Context{
+		W: rr,
+	}
+
+	expected := `{"bar":"bar","taz":30,"car":null}`
+
+	c.JSON(http.StatusOK, Foo{
+		Bar: "bar",
+		Taz: 30,
+		Car: nil,
+	})
+
+	if status := rr.Code; status != http.StatusOK {
+		t.Errorf("Expected status code: %d, Actual: %d", http.StatusOK, status)
+	}
+
+	if rr.Header().Get("Content-Type") != "application/json" {
+		t.Errorf("Expected Content-Type: application/json, Actual: %s", c.W.Header().Get("Content-Type"))
+	}
+
+	if rr.Body.String() != string(expected)+"\n" {
+		t.Errorf("Expected: %s, Actual: %s", string(expected), rr.Body.String())
+	}
+}
+
+func Test_HTML(t *testing.T) {
+	os.Mkdir("templates", os.ModePerm)
+	f, _ := os.Create("templates/page.index.gohtml")
+	f.WriteString("<h1>{{.Data.heading1}}</h1><h2>{{.Data.heading2}}</h2>")
+	f.Close()
+	defer os.RemoveAll("templates")
+
+	rr := httptest.NewRecorder()
+	c := &Context{
+		W: rr,
+		E: &Engine{
+			Renderer: NewHTMLRender(),
+		},
+	}
+
+	expected := `<h1>foo</h1><h2>bar</h2>`
+
+	c.HTML(http.StatusOK, "page.index.gohtml", Data{
+		"heading1": "foo",
+		"heading2": "bar",
+	})
+
+	if status := rr.Code; status != http.StatusOK {
+		t.Errorf("Expected status code: %d, Actual: %d", http.StatusOK, status)
+	}
+
+	if rr.Header().Get("Content-Type") != "text/html; charset=utf-8" {
+		t.Errorf("Expected Content-Type: text/html; charset=utf-8, Actual: %s", c.W.Header().Get("Content-Type"))
+	}
+
+	if rr.Body.String() != string(expected) {
+		t.Errorf("Expected: %s, Actual: %s", string(expected), rr.Body.String())
+	}
+}