diff --git a/openapi3/ref.go b/openapi3/ref.go
index e0d3f03a..71f79601 100644
--- a/openapi3/ref.go
+++ b/openapi3/ref.go
@@ -1,5 +1,9 @@
 package openapi3
 
+import (
+	"context"
+)
+
 //go:generate go run refsgenerator.go
 
 // Ref is specified by OpenAPI/Swagger 3.0 standard.
@@ -8,3 +12,9 @@ type Ref struct {
 	Ref        string         `json:"$ref" yaml:"$ref"`
 	Extensions map[string]any `json:"extensions,omitempty" yaml:"$ref,omitempty"`
 }
+
+// Validate returns an error if Extensions does not comply with the OpenAPI spec.
+func (e *Ref) Validate(ctx context.Context, opts ...ValidationOption) error {
+	ctx = WithValidationOptions(ctx, opts...)
+	return validateExtensions(ctx, e.Extensions)
+}