diff --git a/.github/CODE_OF_CONDUCT.md b/.github/CODE_OF_CONDUCT.md
index b39f08e2d28..82effcdc869 100644
--- a/.github/CODE_OF_CONDUCT.md
+++ b/.github/CODE_OF_CONDUCT.md
@@ -10,4 +10,4 @@ Project maintainers have the right and responsibility to remove, edit, or reject
 
 Instances of abusive, harassing, or otherwise unacceptable behavior may be reported by opening an issue or contacting one or more of the project maintainers.
 
-This Code of Conduct is adapted from the [Contributor Covenant](http://contributor-covenant.org), version 1.0.0, available at [http://contributor-covenant.org/version/1/0/0/](http://contributor-covenant.org/version/1/0/0/)
+This Code of Conduct is adapted from the [Contributor Covenant](https://contributor-covenant.org), version 1.0.0, available at [http://contributor-covenant.org/version/1/0/0/](http://contributor-covenant.org/version/1/0/0/)
diff --git a/.github/CONTRIBUTING.md b/.github/CONTRIBUTING.md
index 3f3302a572e..e4ecadaea68 100644
--- a/.github/CONTRIBUTING.md
+++ b/.github/CONTRIBUTING.md
@@ -36,7 +36,7 @@ Hi! I'm really excited that you are interested in contributing to Vue.js. Before
 
 ## Development Setup
 
-You will need [Node.js](http://nodejs.org) **version 12+** and [pnpm](https://pnpm.io/).
+You will need [Node.js](https://nodejs.org) **version 12+** and [pnpm](https://pnpm.io/).
 
 After cloning the repo, run:
 
diff --git a/examples/classic/todomvc/index.html b/examples/classic/todomvc/index.html
index 504d93597d7..3d9557edf99 100644
--- a/examples/classic/todomvc/index.html
+++ b/examples/classic/todomvc/index.html
@@ -54,8 +54,8 @@ <h1>todos</h1>
     </section>
     <footer class="info">
       <p>Double-click to edit a todo</p>
-      <p>Written by <a href="http://evanyou.me">Evan You</a></p>
-      <p>Part of <a href="http://todomvc.com">TodoMVC</a></p>
+      <p>Written by <a href="https://evanyou.me">Evan You</a></p>
+      <p>Part of <a href="https://todomvc.com">TodoMVC</a></p>
     </footer>
 
     <script>
diff --git a/examples/classic/todomvc/readme.md b/examples/classic/todomvc/readme.md
index 64277f62e9a..db6affe8af7 100644
--- a/examples/classic/todomvc/readme.md
+++ b/examples/classic/todomvc/readme.md
@@ -16,7 +16,7 @@ Here are some links you may find helpful:
 
 Get help from other Vue.js users:
 
-* [Vue.js official forum](http://forum.vuejs.org)
+* [Vue.js official forum](https://forum.vuejs.org)
 * [Vue.js on Twitter](https://twitter.com/vuejs)
 * [Vue.js on Gitter](https://gitter.im/vuejs/vue)
 
@@ -24,4 +24,4 @@ _If you have other helpful links to share, or find any of the links above no lon
 
 ## Credit
 
-This TodoMVC application was created by [Evan You](http://evanyou.me).
+This TodoMVC application was created by [Evan You](https://evanyou.me).
diff --git a/src/compiler/parser/html-parser.ts b/src/compiler/parser/html-parser.ts
index ab24cb52ba7..29acbfc8fc5 100644
--- a/src/compiler/parser/html-parser.ts
+++ b/src/compiler/parser/html-parser.ts
@@ -98,7 +98,7 @@ export function parseHTML(html, options: HTMLParserOptions) {
           }
         }
 
-        // http://en.wikipedia.org/wiki/Conditional_comment#Downlevel-revealed_conditional_comment
+        // https://en.wikipedia.org/wiki/Conditional_comment#Downlevel-revealed_conditional_comment
         if (conditionalComment.test(html)) {
           const conditionalEnd = html.indexOf(']>')
 
diff --git a/src/platforms/web/util/element.ts b/src/platforms/web/util/element.ts
index e5788c4a029..f1df261a355 100644
--- a/src/platforms/web/util/element.ts
+++ b/src/platforms/web/util/element.ts
@@ -62,7 +62,7 @@ export function isUnknownElement(tag: string): boolean {
   }
   const el = document.createElement(tag)
   if (tag.indexOf('-') > -1) {
-    // http://stackoverflow.com/a/28210364/1070244
+    // https://stackoverflow.com/a/28210364/1070244
     return (unknownElementCache[tag] =
       el.constructor === window.HTMLUnknownElement ||
       el.constructor === window.HTMLElement)