diff --git a/packages/react-dev-utils/FileSizeReporter.js b/packages/react-dev-utils/FileSizeReporter.js
index b2b4cc6904d39aee9ada96af7267df40980e3485..cdf3f3b69c8e3e788ff73da41e690747292b4e3b 100644
--- a/packages/react-dev-utils/FileSizeReporter.js
+++ b/packages/react-dev-utils/FileSizeReporter.js
@@ -136,9 +136,9 @@ function measureFileSizesBeforeBuild(buildFolder) {
       var sizes;
       if (!err && fileNames) {
         sizes = fileNames.filter(canReadAsset).reduce((memo, fileName) => {
-          var contents = fs.readFileSync(fileName);
+          var fileStat = fs.statSync(fileName);
           var key = removeFileNameHash(buildFolder, fileName);
-          memo[key] = gzipSize(contents);
+          memo[key] = fileStat.size;
           return memo;
         }, {});
       }