diff --git a/lib/adapters/xhr.js b/lib/adapters/xhr.js
index 0a460e210f..2f22f328d2 100644
--- a/lib/adapters/xhr.js
+++ b/lib/adapters/xhr.js
@@ -58,7 +58,7 @@ export default function xhrAdapter(config) {
       }
     }
 
-    if (utils.isFormData(requestData) && utils.isStandardBrowserEnv()) {
+    if (utils.isFormData(requestData) && platform.isStandardBrowserEnv) {
       requestHeaders.setContentType(false); // Let the browser set it
     }
 
@@ -174,7 +174,7 @@ export default function xhrAdapter(config) {
     // Add xsrf header
     // This is only done if running in a standard browser environment.
     // Specifically not if we're in a web worker, or react-native.
-    if (utils.isStandardBrowserEnv()) {
+    if (platform.isStandardBrowserEnv) {
       // Add xsrf header
       const xsrfValue = (config.withCredentials || isURLSameOrigin(fullPath))
         && config.xsrfCookieName && cookies.read(config.xsrfCookieName);
diff --git a/lib/helpers/cookies.js b/lib/helpers/cookies.js
index 490e67eada..361493a3a4 100644
--- a/lib/helpers/cookies.js
+++ b/lib/helpers/cookies.js
@@ -1,8 +1,9 @@
 'use strict';
 
 import utils from './../utils.js';
+import platform from '../platform/index.js';
 
-export default utils.isStandardBrowserEnv() ?
+export default platform.isStandardBrowserEnv ?
 
 // Standard browser envs support document.cookie
   (function standardBrowserEnv() {
diff --git a/lib/helpers/isURLSameOrigin.js b/lib/helpers/isURLSameOrigin.js
index 9c83902539..18db03b3c5 100644
--- a/lib/helpers/isURLSameOrigin.js
+++ b/lib/helpers/isURLSameOrigin.js
@@ -1,8 +1,9 @@
 'use strict';
 
 import utils from './../utils.js';
+import platform from '../platform/index.js';
 
-export default utils.isStandardBrowserEnv() ?
+export default platform.isStandardBrowserEnv ?
 
 // Standard browser envs have full support of the APIs needed to test
 // whether the request URL is of the same origin as current location.
diff --git a/lib/platform/browser/index.js b/lib/platform/browser/index.js
index df3053bdec..80284eb208 100644
--- a/lib/platform/browser/index.js
+++ b/lib/platform/browser/index.js
@@ -1,6 +1,36 @@
 import URLSearchParams from './classes/URLSearchParams.js'
 import FormData from './classes/FormData.js'
 
+/**
+ * Determine if we're running in a standard browser environment
+ *
+ * This allows axios to run in a web worker, and react-native.
+ * Both environments support XMLHttpRequest, but not fully standard globals.
+ *
+ * web workers:
+ *  typeof window -> undefined
+ *  typeof document -> undefined
+ *
+ * react-native:
+ *  navigator.product -> 'ReactNative'
+ * nativescript
+ *  navigator.product -> 'NativeScript' or 'NS'
+ *
+ * @returns {boolean}
+ */
+const isStandardBrowserEnv = (() => {
+  let product;
+  if (typeof navigator !== 'undefined' && (
+    (product = navigator.product) === 'ReactNative' ||
+    product === 'NativeScript' ||
+    product === 'NS')
+  ) {
+    return false;
+  }
+
+  return typeof window !== 'undefined' && typeof document !== 'undefined';
+})();
+
 export default {
   isBrowser: true,
   classes: {
@@ -8,5 +38,6 @@ export default {
     FormData,
     Blob
   },
+  isStandardBrowserEnv,
   protocols: ['http', 'https', 'file', 'blob', 'url', 'data']
 };
diff --git a/lib/utils.js b/lib/utils.js
index 98b94c0fea..368070f611 100644
--- a/lib/utils.js
+++ b/lib/utils.js
@@ -4,29 +4,20 @@ import bind from './helpers/bind.js';
 
 // utils is a library of generic helper functions non-specific to axios
 
-const toString = Object.prototype.toString;
+const {toString} = Object.prototype;
+const {getPrototypeOf} = Object;
 
-// eslint-disable-next-line func-names
-const kindOf = (cache => {
-  // eslint-disable-next-line func-names
-  return thing => {
+const kindOf = (cache => thing => {
     const str = toString.call(thing);
     return cache[str] || (cache[str] = str.slice(8, -1).toLowerCase());
-  };
 })(Object.create(null));
 
-function kindOfTest(type) {
+const kindOfTest = (type) => {
   type = type.toLowerCase();
-  return function isKindOf(thing) {
-    return kindOf(thing) === type;
-  };
+  return (thing) => kindOf(thing) === type
 }
 
-function typeOfTest(type) {
-  return thing => {
-    return typeof thing === type;
-  };
-}
+const typeOfTest = type => thing => typeof thing === type;
 
 /**
  * Determine if a value is an Array
@@ -35,9 +26,7 @@ function typeOfTest(type) {
  *
  * @returns {boolean} True if value is an Array, otherwise false
  */
-function isArray(val) {
-  return Array.isArray(val);
-}
+const {isArray} = Array;
 
 /**
  * Determine if a value is undefined
@@ -57,7 +46,7 @@ const isUndefined = typeOfTest('undefined');
  */
 function isBuffer(val) {
   return val !== null && !isUndefined(val) && val.constructor !== null && !isUndefined(val.constructor)
-    && typeof val.constructor.isBuffer === 'function' && val.constructor.isBuffer(val);
+    && isFunction(val.constructor.isBuffer) && val.constructor.isBuffer(val);
 }
 
 /**
@@ -120,9 +109,7 @@ const isNumber = typeOfTest('number');
  *
  * @returns {boolean} True if value is an Object, otherwise false
  */
-function isObject(thing) {
-  return thing !== null && typeof thing === 'object';
-}
+const isObject = (thing) => thing !== null && typeof thing === 'object';
 
 /**
  * Determine if a value is a Boolean
@@ -130,9 +117,7 @@ function isObject(thing) {
  * @param {*} thing The value to test
  * @returns {boolean} True if value is a Boolean, otherwise false
  */
-const isBoolean = thing => {
-  return thing === true || thing === false;
-};
+const isBoolean = thing => thing === true || thing === false;
 
 /**
  * Determine if a value is a plain Object
@@ -141,12 +126,12 @@ const isBoolean = thing => {
  *
  * @returns {boolean} True if value is a plain Object, otherwise false
  */
-function isPlainObject(val) {
+const isPlainObject = (val) => {
   if (kindOf(val) !== 'object') {
     return false;
   }
 
-  const prototype = Object.getPrototypeOf(val);
+  const prototype = getPrototypeOf(val);
   return prototype === null || prototype === Object.prototype;
 }
 
@@ -193,9 +178,7 @@ const isFileList = kindOfTest('FileList');
  *
  * @returns {boolean} True if value is a Stream, otherwise false
  */
-function isStream(val) {
-  return isObject(val) && isFunction(val.pipe);
-}
+const isStream = (val) => isObject(val) && isFunction(val.pipe);
 
 /**
  * Determine if a value is a FormData
@@ -204,7 +187,7 @@ function isStream(val) {
  *
  * @returns {boolean} True if value is an FormData, otherwise false
  */
-function isFormData(thing) {
+const isFormData = (thing) => {
   const pattern = '[object FormData]';
   return thing && (
     (typeof FormData === 'function' && thing instanceof FormData) ||
@@ -229,39 +212,8 @@ const isURLSearchParams = kindOfTest('URLSearchParams');
  *
  * @returns {String} The String freed of excess whitespace
  */
-function trim(str) {
-  return str.trim ? str.trim() : str.replace(/^[\s\uFEFF\xA0]+|[\s\uFEFF\xA0]+$/g, '');
-}
-
-/**
- * Determine if we're running in a standard browser environment
- *
- * This allows axios to run in a web worker, and react-native.
- * Both environments support XMLHttpRequest, but not fully standard globals.
- *
- * web workers:
- *  typeof window -> undefined
- *  typeof document -> undefined
- *
- * react-native:
- *  navigator.product -> 'ReactNative'
- * nativescript
- *  navigator.product -> 'NativeScript' or 'NS'
- *
- * @returns {boolean}
- */
-function isStandardBrowserEnv() {
-  let product;
-  if (typeof navigator !== 'undefined' && (
-    (product = navigator.product) === 'ReactNative' ||
-    product === 'NativeScript' ||
-    product === 'NS')
-  ) {
-    return false;
-  }
-
-  return typeof window !== 'undefined' && typeof document !== 'undefined';
-}
+const trim = (str) => str.trim ?
+  str.trim() : str.replace(/^[\s\uFEFF\xA0]+|[\s\uFEFF\xA0]+$/g, '');
 
 /**
  * Iterate over an Array or an Object invoking a function for each item.
@@ -331,7 +283,7 @@ function forEach(obj, fn, {allOwnKeys = false} = {}) {
  */
 function merge(/* obj1, obj2, obj3, ... */) {
   const result = {};
-  function assignValue(val, key) {
+  const assignValue = (val, key) => {
     if (isPlainObject(result[key]) && isPlainObject(val)) {
       result[key] = merge(result[key], val);
     } else if (isPlainObject(val)) {
@@ -359,9 +311,9 @@ function merge(/* obj1, obj2, obj3, ... */) {
  * @param {Boolean} [allOwnKeys]
  * @returns {Object} The resulting value of object a
  */
-function extend(a, b, thisArg, {allOwnKeys}= {}) {
-  forEach(b, function assignValue(val, key) {
-    if (thisArg && typeof val === 'function') {
+const extend = (a, b, thisArg, {allOwnKeys}= {}) => {
+  forEach(b, (val, key) => {
+    if (thisArg && isFunction(val)) {
       a[key] = bind(val, thisArg);
     } else {
       a[key] = val;
@@ -377,7 +329,7 @@ function extend(a, b, thisArg, {allOwnKeys}= {}) {
  *
  * @returns {string} content value without BOM
  */
-function stripBOM(content) {
+const stripBOM = (content) => {
   if (content.charCodeAt(0) === 0xFEFF) {
     content = content.slice(1);
   }
@@ -393,7 +345,7 @@ function stripBOM(content) {
  *
  * @returns {void}
  */
-function inherits(constructor, superConstructor, props, descriptors) {
+const inherits = (constructor, superConstructor, props, descriptors) => {
   constructor.prototype = Object.create(superConstructor.prototype, descriptors);
   constructor.prototype.constructor = constructor;
   Object.defineProperty(constructor, 'super', {
@@ -411,7 +363,7 @@ function inherits(constructor, superConstructor, props, descriptors) {
  *
  * @returns {Object}
  */
-function toFlatObject(sourceObj, destObj, filter, propFilter) {
+const toFlatObject = (sourceObj, destObj, filter, propFilter) => {
   let props;
   let i;
   let prop;
@@ -431,7 +383,7 @@ function toFlatObject(sourceObj, destObj, filter, propFilter) {
         merged[prop] = true;
       }
     }
-    sourceObj = filter !== false && Object.getPrototypeOf(sourceObj);
+    sourceObj = filter !== false && getPrototypeOf(sourceObj);
   } while (sourceObj && (!filter || filter(sourceObj, destObj)) && sourceObj !== Object.prototype);
 
   return destObj;
@@ -446,7 +398,7 @@ function toFlatObject(sourceObj, destObj, filter, propFilter) {
  *
  * @returns {boolean}
  */
-function endsWith(str, searchString, position) {
+const endsWith = (str, searchString, position) => {
   str = String(str);
   if (position === undefined || position > str.length) {
     position = str.length;
@@ -464,7 +416,7 @@ function endsWith(str, searchString, position) {
  *
  * @returns {?Array}
  */
-function toArray(thing) {
+const toArray = (thing) => {
   if (!thing) return null;
   if (isArray(thing)) return thing;
   let i = thing.length;
@@ -490,7 +442,7 @@ const isTypedArray = (TypedArray => {
   return thing => {
     return TypedArray && thing instanceof TypedArray;
   };
-})(typeof Uint8Array !== 'undefined' && Object.getPrototypeOf(Uint8Array));
+})(typeof Uint8Array !== 'undefined' && getPrototypeOf(Uint8Array));
 
 /**
  * For each entry in the object, call the function with the key and value.
@@ -500,7 +452,7 @@ const isTypedArray = (TypedArray => {
  *
  * @returns {void}
  */
-function forEachEntry(obj, fn) {
+const forEachEntry = (obj, fn) => {
   const generator = obj && obj[Symbol.iterator];
 
   const iterator = generator.call(obj);
@@ -521,7 +473,7 @@ function forEachEntry(obj, fn) {
  *
  * @returns {Array<boolean>}
  */
-function matchAll(regExp, str) {
+const matchAll = (regExp, str) => {
   let matches;
   const arr = [];
 
@@ -544,11 +496,7 @@ const toCamelCase = str => {
 };
 
 /* Creating a function that will check if an object has a property. */
-const hasOwnProperty = (function resolver(_hasOwnProperty) {
-  return (obj, prop) => {
-    return _hasOwnProperty.call(obj, prop);
-  };
-})(Object.prototype.hasOwnProperty);
+const hasOwnProperty = (({hasOwnProperty}) => (obj, prop) => hasOwnProperty.call(obj, prop))(Object.prototype);
 
 /**
  * Determine if a value is a RegExp object
@@ -559,7 +507,7 @@ const hasOwnProperty = (function resolver(_hasOwnProperty) {
  */
 const isRegExp = kindOfTest('RegExp');
 
-function reduceDescriptors(obj, reducer) {
+const reduceDescriptors = (obj, reducer) => {
   const descriptors = Object.getOwnPropertyDescriptors(obj);
   const reducedDescriptors = {};
 
@@ -577,7 +525,7 @@ function reduceDescriptors(obj, reducer) {
  * @param {Object} obj
  */
 
-function freezeMethods(obj) {
+const freezeMethods = (obj) => {
   reduceDescriptors(obj, (descriptor, name) => {
     const value = obj[name];
 
@@ -598,10 +546,10 @@ function freezeMethods(obj) {
   });
 }
 
-function toObjectSet(arrayOrString, delimiter) {
+const toObjectSet = (arrayOrString, delimiter) => {
   const obj = {};
 
-  function define(arr) {
+  const define = (arr) => {
     arr.forEach(value => {
       obj[value] = true;
     });
@@ -612,9 +560,9 @@ function toObjectSet(arrayOrString, delimiter) {
   return obj;
 }
 
-function noop() {}
+const noop = () => {}
 
-function toFiniteNumber(value, defaultValue) {
+const toFiniteNumber = (value, defaultValue) => {
   value = +value;
   return Number.isFinite(value) ? value : defaultValue;
 }
@@ -640,7 +588,6 @@ export default {
   isURLSearchParams,
   isTypedArray,
   isFileList,
-  isStandardBrowserEnv,
   forEach,
   merge,
   extend,
diff --git a/package-lock.json b/package-lock.json
index d7858cfd5c..3dae473be7 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -50,6 +50,7 @@
         "multer": "^1.4.4",
         "rollup": "^2.67.0",
         "rollup-plugin-auto-external": "^2.0.0",
+        "rollup-plugin-bundle-size": "^1.0.3",
         "rollup-plugin-terser": "^7.0.2",
         "sinon": "^4.5.0",
         "stream-throttle": "^0.1.3",
@@ -6281,6 +6282,12 @@
         "universalify": "^0.1.0"
       }
     },
+    "node_modules/duplexer": {
+      "version": "0.1.1",
+      "resolved": "https://registry.npmjs.org/duplexer/-/duplexer-0.1.1.tgz",
+      "integrity": "sha512-sxNZ+ljy+RA1maXoUReeqBBpBC6RLKmg5ewzV+x+mSETmWNoKdZN6vcQjpFROemza23hGFskJtFNoUWUaQ+R4Q==",
+      "dev": true
+    },
     "node_modules/duplexer3": {
       "version": "0.1.4",
       "resolved": "https://registry.npmjs.org/duplexer3/-/duplexer3-0.1.4.tgz",
@@ -6424,6 +6431,31 @@
         "node": ">= 0.8"
       }
     },
+    "node_modules/encoding": {
+      "version": "0.1.13",
+      "resolved": "https://registry.npmjs.org/encoding/-/encoding-0.1.13.tgz",
+      "integrity": "sha512-ETBauow1T35Y/WZMkio9jiM0Z5xjHHmJ4XmjZOq1l/dXz3lr2sRn87nJy20RupqSh1F2m3HHPSp8ShIPQJrJ3A==",
+      "dev": true,
+      "optional": true,
+      "peer": true,
+      "dependencies": {
+        "iconv-lite": "^0.6.2"
+      }
+    },
+    "node_modules/encoding/node_modules/iconv-lite": {
+      "version": "0.6.3",
+      "resolved": "https://registry.npmjs.org/iconv-lite/-/iconv-lite-0.6.3.tgz",
+      "integrity": "sha512-4fCk79wshMdzMp2rH06qWrJE4iolqLhCUH+OiuIgU++RB0+94NlDL81atO7GX55uUKueo0txHNtvEyI6D7WdMw==",
+      "dev": true,
+      "optional": true,
+      "peer": true,
+      "dependencies": {
+        "safer-buffer": ">= 2.1.2 < 3.0.0"
+      },
+      "engines": {
+        "node": ">=0.10.0"
+      }
+    },
     "node_modules/end-of-stream": {
       "version": "1.4.4",
       "resolved": "https://registry.npmjs.org/end-of-stream/-/end-of-stream-1.4.4.tgz",
@@ -7549,6 +7581,19 @@
       "dev": true,
       "peer": true
     },
+    "node_modules/figures": {
+      "version": "1.7.0",
+      "resolved": "https://registry.npmjs.org/figures/-/figures-1.7.0.tgz",
+      "integrity": "sha512-UxKlfCRuCBxSXU4C6t9scbDyWZ4VlaFFdojKtzJuSkuOBQ5CNFum+zZXFwHjo+CxBC1t6zlYPgHIgFjL8ggoEQ==",
+      "dev": true,
+      "dependencies": {
+        "escape-string-regexp": "^1.0.5",
+        "object-assign": "^4.1.0"
+      },
+      "engines": {
+        "node": ">=0.10.0"
+      }
+    },
     "node_modules/file-entry-cache": {
       "version": "6.0.1",
       "resolved": "https://registry.npmjs.org/file-entry-cache/-/file-entry-cache-6.0.1.tgz",
@@ -11038,6 +11083,33 @@
         "url": "https://github.com/sponsors/sindresorhus"
       }
     },
+    "node_modules/maxmin": {
+      "version": "2.1.0",
+      "resolved": "https://registry.npmjs.org/maxmin/-/maxmin-2.1.0.tgz",
+      "integrity": "sha512-NWlApBjW9az9qRPaeg7CX4sQBWwytqz32bIEo1PW9pRW+kBP9KLRfJO3UC+TV31EcQZEUq7eMzikC7zt3zPJcw==",
+      "dev": true,
+      "dependencies": {
+        "chalk": "^1.0.0",
+        "figures": "^1.0.1",
+        "gzip-size": "^3.0.0",
+        "pretty-bytes": "^3.0.0"
+      },
+      "engines": {
+        "node": ">=0.12"
+      }
+    },
+    "node_modules/maxmin/node_modules/gzip-size": {
+      "version": "3.0.0",
+      "resolved": "https://registry.npmjs.org/gzip-size/-/gzip-size-3.0.0.tgz",
+      "integrity": "sha512-6s8trQiK+OMzSaCSVXX+iqIcLV9tC+E73jrJrJTyS4h/AJhlxHvzFKqM1YLDJWRGgHX8uLkBeXkA0njNj39L4w==",
+      "dev": true,
+      "dependencies": {
+        "duplexer": "^0.1.1"
+      },
+      "engines": {
+        "node": ">=0.12.0"
+      }
+    },
     "node_modules/md5.js": {
       "version": "1.3.5",
       "resolved": "https://registry.npmjs.org/md5.js/-/md5.js-1.3.5.tgz",
@@ -13150,6 +13222,18 @@
         "node": ">=4"
       }
     },
+    "node_modules/pretty-bytes": {
+      "version": "3.0.1",
+      "resolved": "https://registry.npmjs.org/pretty-bytes/-/pretty-bytes-3.0.1.tgz",
+      "integrity": "sha512-eb7ZAeUTgfh294cElcu51w+OTRp/6ItW758LjwJSK72LDevcuJn0P4eD71PLMDGPwwatXmAmYHTkzvpKlJE3ow==",
+      "dev": true,
+      "dependencies": {
+        "number-is-nan": "^1.0.0"
+      },
+      "engines": {
+        "node": ">=0.10.0"
+      }
+    },
     "node_modules/pretty-hrtime": {
       "version": "1.0.3",
       "resolved": "https://registry.npmjs.org/pretty-hrtime/-/pretty-hrtime-1.0.3.tgz",
@@ -14146,6 +14230,16 @@
         "node": ">=4"
       }
     },
+    "node_modules/rollup-plugin-bundle-size": {
+      "version": "1.0.3",
+      "resolved": "https://registry.npmjs.org/rollup-plugin-bundle-size/-/rollup-plugin-bundle-size-1.0.3.tgz",
+      "integrity": "sha512-aWj0Pvzq90fqbI5vN1IvUrlf4utOqy+AERYxwWjegH1G8PzheMnrRIgQ5tkwKVtQMDP0bHZEACW/zLDF+XgfXQ==",
+      "dev": true,
+      "dependencies": {
+        "chalk": "^1.1.3",
+        "maxmin": "^2.1.0"
+      }
+    },
     "node_modules/rollup-plugin-terser": {
       "version": "7.0.2",
       "resolved": "https://registry.npmjs.org/rollup-plugin-terser/-/rollup-plugin-terser-7.0.2.tgz",
@@ -23012,6 +23106,12 @@
         }
       }
     },
+    "duplexer": {
+      "version": "0.1.1",
+      "resolved": "https://registry.npmjs.org/duplexer/-/duplexer-0.1.1.tgz",
+      "integrity": "sha512-sxNZ+ljy+RA1maXoUReeqBBpBC6RLKmg5ewzV+x+mSETmWNoKdZN6vcQjpFROemza23hGFskJtFNoUWUaQ+R4Q==",
+      "dev": true
+    },
     "duplexer3": {
       "version": "0.1.4",
       "resolved": "https://registry.npmjs.org/duplexer3/-/duplexer3-0.1.4.tgz",
@@ -23153,6 +23253,30 @@
       "integrity": "sha1-rT/0yG7C0CkyL1oCw6mmBslbP1k=",
       "dev": true
     },
+    "encoding": {
+      "version": "0.1.13",
+      "resolved": "https://registry.npmjs.org/encoding/-/encoding-0.1.13.tgz",
+      "integrity": "sha512-ETBauow1T35Y/WZMkio9jiM0Z5xjHHmJ4XmjZOq1l/dXz3lr2sRn87nJy20RupqSh1F2m3HHPSp8ShIPQJrJ3A==",
+      "dev": true,
+      "optional": true,
+      "peer": true,
+      "requires": {
+        "iconv-lite": "^0.6.2"
+      },
+      "dependencies": {
+        "iconv-lite": {
+          "version": "0.6.3",
+          "resolved": "https://registry.npmjs.org/iconv-lite/-/iconv-lite-0.6.3.tgz",
+          "integrity": "sha512-4fCk79wshMdzMp2rH06qWrJE4iolqLhCUH+OiuIgU++RB0+94NlDL81atO7GX55uUKueo0txHNtvEyI6D7WdMw==",
+          "dev": true,
+          "optional": true,
+          "peer": true,
+          "requires": {
+            "safer-buffer": ">= 2.1.2 < 3.0.0"
+          }
+        }
+      }
+    },
     "end-of-stream": {
       "version": "1.4.4",
       "resolved": "https://registry.npmjs.org/end-of-stream/-/end-of-stream-1.4.4.tgz",
@@ -24073,6 +24197,16 @@
       "dev": true,
       "peer": true
     },
+    "figures": {
+      "version": "1.7.0",
+      "resolved": "https://registry.npmjs.org/figures/-/figures-1.7.0.tgz",
+      "integrity": "sha512-UxKlfCRuCBxSXU4C6t9scbDyWZ4VlaFFdojKtzJuSkuOBQ5CNFum+zZXFwHjo+CxBC1t6zlYPgHIgFjL8ggoEQ==",
+      "dev": true,
+      "requires": {
+        "escape-string-regexp": "^1.0.5",
+        "object-assign": "^4.1.0"
+      }
+    },
     "file-entry-cache": {
       "version": "6.0.1",
       "resolved": "https://registry.npmjs.org/file-entry-cache/-/file-entry-cache-6.0.1.tgz",
@@ -26890,6 +27024,29 @@
         }
       }
     },
+    "maxmin": {
+      "version": "2.1.0",
+      "resolved": "https://registry.npmjs.org/maxmin/-/maxmin-2.1.0.tgz",
+      "integrity": "sha512-NWlApBjW9az9qRPaeg7CX4sQBWwytqz32bIEo1PW9pRW+kBP9KLRfJO3UC+TV31EcQZEUq7eMzikC7zt3zPJcw==",
+      "dev": true,
+      "requires": {
+        "chalk": "^1.0.0",
+        "figures": "^1.0.1",
+        "gzip-size": "^3.0.0",
+        "pretty-bytes": "^3.0.0"
+      },
+      "dependencies": {
+        "gzip-size": {
+          "version": "3.0.0",
+          "resolved": "https://registry.npmjs.org/gzip-size/-/gzip-size-3.0.0.tgz",
+          "integrity": "sha512-6s8trQiK+OMzSaCSVXX+iqIcLV9tC+E73jrJrJTyS4h/AJhlxHvzFKqM1YLDJWRGgHX8uLkBeXkA0njNj39L4w==",
+          "dev": true,
+          "requires": {
+            "duplexer": "^0.1.1"
+          }
+        }
+      }
+    },
     "md5.js": {
       "version": "1.3.5",
       "resolved": "https://registry.npmjs.org/md5.js/-/md5.js-1.3.5.tgz",
@@ -28634,6 +28791,15 @@
       "integrity": "sha1-6SQ0v6XqjBn0HN/UAddBo8gZ2Jc=",
       "dev": true
     },
+    "pretty-bytes": {
+      "version": "3.0.1",
+      "resolved": "https://registry.npmjs.org/pretty-bytes/-/pretty-bytes-3.0.1.tgz",
+      "integrity": "sha512-eb7ZAeUTgfh294cElcu51w+OTRp/6ItW758LjwJSK72LDevcuJn0P4eD71PLMDGPwwatXmAmYHTkzvpKlJE3ow==",
+      "dev": true,
+      "requires": {
+        "number-is-nan": "^1.0.0"
+      }
+    },
     "pretty-hrtime": {
       "version": "1.0.3",
       "resolved": "https://registry.npmjs.org/pretty-hrtime/-/pretty-hrtime-1.0.3.tgz",
@@ -29446,6 +29612,16 @@
         }
       }
     },
+    "rollup-plugin-bundle-size": {
+      "version": "1.0.3",
+      "resolved": "https://registry.npmjs.org/rollup-plugin-bundle-size/-/rollup-plugin-bundle-size-1.0.3.tgz",
+      "integrity": "sha512-aWj0Pvzq90fqbI5vN1IvUrlf4utOqy+AERYxwWjegH1G8PzheMnrRIgQ5tkwKVtQMDP0bHZEACW/zLDF+XgfXQ==",
+      "dev": true,
+      "requires": {
+        "chalk": "^1.1.3",
+        "maxmin": "^2.1.0"
+      }
+    },
     "rollup-plugin-terser": {
       "version": "7.0.2",
       "resolved": "https://registry.npmjs.org/rollup-plugin-terser/-/rollup-plugin-terser-7.0.2.tgz",
diff --git a/package.json b/package.json
index 85d7491833..e21ab3dbc7 100644
--- a/package.json
+++ b/package.json
@@ -88,6 +88,7 @@
     "multer": "^1.4.4",
     "rollup": "^2.67.0",
     "rollup-plugin-auto-external": "^2.0.0",
+    "rollup-plugin-bundle-size": "^1.0.3",
     "rollup-plugin-terser": "^7.0.2",
     "sinon": "^4.5.0",
     "stream-throttle": "^0.1.3",
@@ -129,4 +130,4 @@
     "Ben Carp (https://github.com/carpben)",
     "Daniel Lopretto (https://github.com/timemachine3030)"
   ]
-}
\ No newline at end of file
+}
diff --git a/rollup.config.js b/rollup.config.js
index c694865757..9fd12d1bac 100644
--- a/rollup.config.js
+++ b/rollup.config.js
@@ -4,6 +4,7 @@ import {terser} from "rollup-plugin-terser";
 import json from '@rollup/plugin-json';
 import { babel } from '@rollup/plugin-babel';
 import autoExternal from 'rollup-plugin-auto-external';
+import bundleSize from 'rollup-plugin-bundle-size'
 
 const lib = require("./package.json");
 const outputFileName = 'axios';
@@ -24,6 +25,7 @@ const buildConfig = ({es5, browser = true, minifiedVersion = true, ...config}) =
       resolve({browser}),
       commonjs(),
       minified && terser(),
+      minified && bundleSize(),
       ...(es5 ? [babel({
         babelHelpers: 'bundled',
         presets: ['@babel/preset-env']
@@ -37,7 +39,7 @@ const buildConfig = ({es5, browser = true, minifiedVersion = true, ...config}) =
   ];
 
   if (minifiedVersion) {
-    build({minified: true})
+    configs.push(build({minified: true}))
   }
 
   return configs;