diff --git a/composer.json b/composer.json
index 79342f5..5a4e3b5 100644
--- a/composer.json
+++ b/composer.json
@@ -14,7 +14,7 @@
     }
   ],
   "require": {
-    "php": ">=7.1",
+    "php": ">=7.0",
     "starkbank/ecdsa": "^0.0.5"
   },
   "keywords": [