diff --git a/recaptcha.go b/recaptcha.go
index 32004f0..9db56f2 100644
--- a/recaptcha.go
+++ b/recaptcha.go
@@ -9,9 +9,9 @@ import (
 )
 
 func validateRecaptcha(token string) (bool, error) {
-	secret := os.Getenv("RECAPTCHA_SECRET_KEY")
+	secret := os.Getenv("CAPTCHA_SERVER_KEY")
 	if secret == "" {
-		return false, errors.New("missing RECAPTCHA_SECRET_KEY")
+		return false, errors.New("missing CAPTCHA_SERVER_KEY")
 	}
 
 	url := "https://www.google.com/recaptcha/api/siteverify"