diff --git a/README.md b/README.md
index e471f49f..f6c24352 100644
--- a/README.md
+++ b/README.md
@@ -110,6 +110,7 @@ Following options available for the JS Obfuscator:
     debugProtectionInterval: false,
     disableConsoleOutput: true,
     encodeUnicodeLiterals: false,
+    optimize: false,
     reservedNames: [],
     rotateUnicodeArray: true,
     selfDefending: true,
@@ -135,6 +136,7 @@ Following options available for the JS Obfuscator:
     --debugProtectionInterval <boolean>
     --disableConsoleOutput <boolean>
     --encodeUnicodeLiterals <boolean>
+    --optimize <boolean>
     --reservedNames <list> (comma separated)
     --rotateUnicodeArray <boolean>
     --selfDefending <boolean>
@@ -186,6 +188,11 @@ This option can slightly slow down your code speed.
 All literals in Unicode array become encoded in Base64.
 To decode strings, a special function will be inserted on the page under `unicodeArray` node.
 
+### `optimize`
+Type: `boolean` Default: `false`
+
+Enables optimizations for obfuscated code with help of [optimize-js](https://github.com/nolanlawson/optimize-js)
+
 ### `reservedNames`
 Type: `string[]` Default: `[]`
 
diff --git a/dist/index.js b/dist/index.js
index 8003cba2..3299bf63 100644
--- a/dist/index.js
+++ b/dist/index.js
@@ -1069,7 +1069,7 @@ exports.DEFAULT_PRESET = Object.freeze({
     disableConsoleOutput: true,
     domainLock: [],
     encodeUnicodeLiterals: false,
-    optimize: true,
+    optimize: false,
     reservedNames: [],
     rotateUnicodeArray: true,
     selfDefending: true,
@@ -1544,7 +1544,7 @@ var JavaScriptObfuscatorCLI = function () {
     }, {
         key: 'configureCommands',
         value: function configureCommands() {
-            this.commands = new commander.Command().version(JavaScriptObfuscatorCLI.getBuildVersion(), '-v, --version').usage('<inputPath> [options]').option('-o, --output <path>', 'Output path for obfuscated code').option('--compact <boolean>', 'Disable one line output code compacting', JavaScriptObfuscatorCLI.parseBoolean).option('--debugProtection <boolean>', 'Disable browser Debug panel (can cause DevTools enabled browser freeze)', JavaScriptObfuscatorCLI.parseBoolean).option('--debugProtectionInterval <boolean>', 'Disable browser Debug panel even after page was loaded (can cause DevTools enabled browser freeze)', JavaScriptObfuscatorCLI.parseBoolean).option('--disableConsoleOutput <boolean>', 'Allow console.log, console.info, console.error and console.warn messages output into browser console', JavaScriptObfuscatorCLI.parseBoolean).option('--encodeUnicodeLiterals <boolean>', 'All literals in Unicode array become encoded in Base64 (this option can slightly slow down your code speed)', JavaScriptObfuscatorCLI.parseBoolean).option('--reservedNames <list>', 'Disable obfuscation of variable names, function names and names of function parameters that match the passed RegExp patterns (comma separated)', function (val) {
+            this.commands = new commander.Command().version(JavaScriptObfuscatorCLI.getBuildVersion(), '-v, --version').usage('<inputPath> [options]').option('-o, --output <path>', 'Output path for obfuscated code').option('--compact <boolean>', 'Disable one line output code compacting', JavaScriptObfuscatorCLI.parseBoolean).option('--debugProtection <boolean>', 'Disable browser Debug panel (can cause DevTools enabled browser freeze)', JavaScriptObfuscatorCLI.parseBoolean).option('--debugProtectionInterval <boolean>', 'Disable browser Debug panel even after page was loaded (can cause DevTools enabled browser freeze)', JavaScriptObfuscatorCLI.parseBoolean).option('--disableConsoleOutput <boolean>', 'Allow console.log, console.info, console.error and console.warn messages output into browser console', JavaScriptObfuscatorCLI.parseBoolean).option('--encodeUnicodeLiterals <boolean>', 'All literals in Unicode array become encoded in Base64 (this option can slightly slow down your code speed)', JavaScriptObfuscatorCLI.parseBoolean).option('--optimize <boolean>', 'Enables optimizations for obfuscated code with help of `optimize-js`', JavaScriptObfuscatorCLI.parseBoolean).option('--reservedNames <list>', 'Disable obfuscation of variable names, function names and names of function parameters that match the passed RegExp patterns (comma separated)', function (val) {
                 return val.split(',');
             }).option('--rotateUnicodeArray <boolean>', 'Disable rotation of unicode array values during obfuscation', JavaScriptObfuscatorCLI.parseBoolean).option('--selfDefending <boolean>', 'Disables self-defending for obfuscated code', JavaScriptObfuscatorCLI.parseBoolean).option('--sourceMap <boolean>', 'Enables source map generation', JavaScriptObfuscatorCLI.parseBoolean).option('--sourceMapBaseUrl <string>', 'Sets base url to the source map import url when `--sourceMapMode=separate`').option('--sourceMapFileName <string>', 'Sets file name for output source map when `--sourceMapMode=separate`').option('--sourceMapMode <string> [inline, separate]', 'Specify source map output mode', JavaScriptObfuscatorCLI.parseSourceMapMode).option('--unicodeArray <boolean>', 'Disables gathering of all literal strings into an array and replacing every literal string with an array call', JavaScriptObfuscatorCLI.parseBoolean).option('--unicodeArrayThreshold <number>', 'The probability that the literal string will be inserted into unicodeArray (Default: 0.8, Min: 0, Max: 1)', parseFloat).option('--wrapUnicodeArrayCalls <boolean>', 'Disables usage of special access function instead of direct array call', JavaScriptObfuscatorCLI.parseBoolean).option('--domainLock <list>', 'Blocks the execution of the code in domains that do not match the passed RegExp patterns (comma separated)', function (val) {
                 return val.split(',');
diff --git a/src/cli/JavaScriptObfuscatorCLI.ts b/src/cli/JavaScriptObfuscatorCLI.ts
index 4a4453c4..8fa81be6 100644
--- a/src/cli/JavaScriptObfuscatorCLI.ts
+++ b/src/cli/JavaScriptObfuscatorCLI.ts
@@ -127,6 +127,7 @@ export class JavaScriptObfuscatorCLI {
             .option('--debugProtectionInterval <boolean>', 'Disable browser Debug panel even after page was loaded (can cause DevTools enabled browser freeze)', JavaScriptObfuscatorCLI.parseBoolean)
             .option('--disableConsoleOutput <boolean>', 'Allow console.log, console.info, console.error and console.warn messages output into browser console', JavaScriptObfuscatorCLI.parseBoolean)
             .option('--encodeUnicodeLiterals <boolean>', 'All literals in Unicode array become encoded in Base64 (this option can slightly slow down your code speed)', JavaScriptObfuscatorCLI.parseBoolean)
+            .option('--optimize <boolean>', 'Enables optimizations for obfuscated code with help of `optimize-js`', JavaScriptObfuscatorCLI.parseBoolean)
             .option('--reservedNames <list>', 'Disable obfuscation of variable names, function names and names of function parameters that match the passed RegExp patterns (comma separated)', (val: string) => val.split(','))
             .option('--rotateUnicodeArray <boolean>', 'Disable rotation of unicode array values during obfuscation', JavaScriptObfuscatorCLI.parseBoolean)
             .option('--selfDefending <boolean>', 'Disables self-defending for obfuscated code', JavaScriptObfuscatorCLI.parseBoolean)
diff --git a/src/preset-options/DefaultPreset.ts b/src/preset-options/DefaultPreset.ts
index bf1747e5..2a784a4f 100644
--- a/src/preset-options/DefaultPreset.ts
+++ b/src/preset-options/DefaultPreset.ts
@@ -9,7 +9,7 @@ export const DEFAULT_PRESET: IObfuscatorOptions = Object.freeze({
     disableConsoleOutput: true,
     domainLock: [],
     encodeUnicodeLiterals: false,
-    optimize: true,
+    optimize: false,
     reservedNames: [],
     rotateUnicodeArray: true,
     selfDefending: true,