diff --git a/coretool.js b/coretool.js
index 9ee6f06..cfdc93b 100644
--- a/coretool.js
+++ b/coretool.js
@@ -296,4 +296,8 @@ module.exports = {
       return sortType ? ~~(a[key] < b[key]) : ~~(a[key] > b[key])
     }
   },
+
+  number_precision (number, precision = 4) {
+    return Number(Number(number).toFixed(precision))
+  },
 }