Top 20+ VueJS Interview Questions and Answers

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Vue.js is a popular JavaScript framework used to build fast and user-friendly web interfaces. It was created in 2014 by Evan You, a former Google engineer. He wanted something lightweight and flexible after working with AngularJS. Over the years, Vue.js has grown with strong community support and applications. Today, many companies use it for building modern frontend apps. If you are applying for a frontend role, knowing Vue.js is a big plus. Here is a list of the top 20+ Vuejs interview questions and answers to help you prepare.

Fun Fact – Vue.js has over 204,000 stars on GitHub, making it one of the most loved JavaScript frameworks.

VueJS Interview Questions for Freshers

Here are some of the most commonly asked Vue.js interview questions and answers for freshers and recent graduates.  

1. What is Vue.js?

Vue.js is a modern JavaScript framework used to build user interfaces and single-page applications. It focuses on the view layer and is known for being simple, lightweight, and flexible. 

2. How does Vue.js differ from other frameworks?

Vue is easier to learn than Angular or React. It uses a template-based syntax and does not require JSX. While Angular is opinionated and React is component-driven, Vue gives more freedom and balances both.

3. What are the key features of Vue.js?

Here are the main features of Vue.js –

• Reactive two-way data binding
• Uses a virtual DOM for fast updates
• Component-based architecture
• Built-in support for transitions and animations
• Easy routing with Vue Router
• State management with Vuex or Pinia
• Works well for both small and large projects

4. What is a single-page application in Vue.js?

A single-page application (SPA) loads once and updates content dynamically without refreshing the whole page. In Vue, SPAs are built using Vue Router to handle navigation between views.

5. Explain two-way data binding using v-model.

v-model creates a two-way connection between form inputs and component data. When I type into an input field, the value in the data object updates instantly, and vice versa.

6. What are directives in Vue.js and give examples?

Directives are special markers in templates that tell Vue to do something with the DOM. 

Examples include –

• v-if for conditional rendering
• v-for for looping through lists
• v-bind to bind attributes
• v-model for two-way binding

They are simple but powerful tools in Vue.

7. What is the virtual DOM and how does Vue use it?

The virtual DOM is a lightweight copy of the actual DOM. When data changes, Vue updates this virtual copy first. It then compares it with the old one to find what really changed. After that, only the changed parts of the real DOM get updated. This speeds up performance and avoids unnecessary re-rendering.

VueJS Interview Questions for Experienced

This section covers Vue.js senior interview questions commonly asked in experienced-level technical rounds.

8. How do you manage state in Vue using Vuex or Pinia?

Vuex and Pinia are state management tools. Vuex uses mutations and actions, while Pinia is more modern and simpler with direct state updates. In 2025, Pinia is officially recommended and better with Vue 3’s Composition API.

9. Explain mixins and their pros and cons.

Mixins are a way to reuse code across multiple Vue components. You can define common methods, data, or lifecycle hooks in a mixin and then use it in different components. The mixin logic gets merged into the component where it is used.

Pros	Cons
Reuse logic across components	Naming conflicts may occur
Keeps code DRY and cleaner	Hard to trace where logic comes from
Easy to implement in small projects	Difficult to debug in large codebases
Useful for shared functionality	Logic gets mixed into components silently

10. How do you optimize a large list rendering in Vue?

Use v-show over v-if for toggling visibility, and avoid unnecessary DOM updates. For huge lists, I use virtual scrolling libraries like vue-virtual-scroller. Also, always add a unique key in v-for for better diffing.

11. What are navigation guards in Vue Router and how do you use them?

Navigation guards control access to routes. They help run logic before entering or leaving a page. For example, I use router.beforeEach() to check if a user is logged in before loading a route. There are also per-route and in-component guards.

12. How do watchers differ from computed properties in Vue?

Computed properties are cached. They run only when dependencies change. Watchers are used when I need to run side effects, like an API call after a value changes.

13. How do you handle global error handling in Vue applications?

I use app.config.errorHandler in Vue 3 to catch errors globally. It logs issues or shows fallback UI. For async code, I wrap await calls in try/catch blocks.

VueJS Technical Interview Questions

14. How does Server-Side Rendering (SSR) work in Vue with Nuxt?

SSR means rendering Vue components on the server, then sending HTML to the browser. Nuxt makes this easier by handling routing, hydration, and server-side logic out of the box. It boosts initial load speed and SEO.

15. Explain the Composition API and when to use it over Options API.

The Composition API lets you group related logic together using setup(). It’s great for code reuse and cleaner components. I use it when components get too big or when writing reusable logic across multiple files.

16. How do you clean up third-party plugin instances to avoid memory leaks?

When I use external libraries like charts or maps, I clean them up in the onUnmounted() hook. I also remove event listeners or destroy timers if they’re set during onMounted().

17. How do you profile and optimize performance in a Vue app?

I use Vue Devtools for inspecting reactivity and render times. I avoid unnecessary watchers and use v-show instead of v-if for toggles. Lazy loading, using key in loops, and keeping component trees small also help.

Also Read - Top 50+ HTML Interview Questions and Answers

VueJS Coding Interview Questions

These are practical Vue.js interview questions designed to test your coding skills and real-world knowledge.

18. Build a reusable input component using v-model and conditional rendering. 

<!– BaseInput.vue –>

<template>

  <div>

    <input :value=”modelValue” @input=”$emit(‘update:modelValue’, $event.target.value)” />

    <p v-if=”!modelValue” style=”color: red”>This field is required.</p>

  </div>

</template>

<script setup>

defineProps([‘modelValue’])

defineEmits([‘update:modelValue’])

</script>

Usage:

<BaseInput v-model=”name” />

19. Debounce a search input to delay API calls in a component.

<script setup>

import { ref, watch } from ‘vue’

const search = ref(”)

const result = ref(”)

let timeout

watch(search, (newVal) => {

  clearTimeout(timeout)

  timeout = setTimeout(() => {

    fetchData(newVal)

  }, 300)

})

function fetchData(query) {

  // call API here

  result.value = `Results for ${query}`

}

</script>

<template>

  <input v-model=”search” placeholder=”Search…” />

  <p>{{ result }}</p>

</template>

20. Implement a dynamic list where styling depends on data.

<template>

  <ul>

    <li v-for=”item in items” :key=”item.id” :class=”{ done: item.done }”>

      {{ item.name }}

    </li>

  </ul>

</template>

<script setup>

const items = [

  { id: 1, name: ‘Task A’, done: false },

  { id: 2, name: ‘Task B’, done: true }

]

</script>

<style>

.done {

  text-decoration: line-through;

  color: gray;

}

</style>

21. Write a component that fetches data when a prop changes (using a watcher).

<script setup>

import { ref, watch } from ‘vue’

const props = defineProps([‘userId’])

const userData = ref(null)

watch(() => props.userId, async (newId) => {

  const res = await fetch(`https://api.example.com/user/${newId}`)

  userData.value = await res.json()

})

</script>

<template>

  <div v-if=”userData”>

    <h3>{{ userData.name }}</h3>

  </div>

</template>

How to Prepare for VueJS Interview?

Follow these tips to improve your chances and show real Vue.js skills in a technical interview.

• Practice Composition API with real examples
• Use Pinia for state in a sample project
• Write a watcher that triggers an API call
• Learn to debug with Vue Devtools
• Build one Nuxt app with SSR and routing
• Talk about what you have built and why

Also Read - Top 60+ JavaScript Interview Questions and Answers

Wrapping Up

So, these are the top VueJS interview questions and answers to help you prepare easily. Keep your concepts clear and practice coding challenges. The more hands-on you are, the better you will perform.

Looking for Vue.js developer jobs? Visit Hirist – a platform filled with top IT job openings, including roles that need Vue skills.

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