diff --git a/oauth2.go b/oauth2.go
index bcefc11..df17194 100644
--- a/oauth2.go
+++ b/oauth2.go
@@ -291,6 +291,19 @@ func (tf *TokenRefresher) Token() (*Token, error) {
 	return tk, err
 }
 
+func RefreshToken(ctx context.Context, conf *Config, refreshToken string) (*Token, error) {
+	if refreshToken == "" {
+		return nil, errors.New("oauth2: token expired and refresh token is not set")
+	}
+
+	tk, err := retrieveToken(ctx, conf, url.Values{
+		"grant_type":    {"refresh_token"},
+		"refresh_token": {refreshToken},
+	})
+
+	return tk, err
+}
+
 // tokenRefresher is a TokenSource that makes "grant_type"=="refresh_token"
 // HTTP requests to renew a token using a RefreshToken.
 type tokenRefresher struct {