Free Frontend Developer Practice Assessment (2026)

Cohesyve · Practice for candidates

Going for a Frontend Developer role? Find out how you'd actually score.

Run a Frontend Developer simulation built the same way employers build theirs, and get a full report showing exactly where you lost marks — before it counts.

free assessments a month

no card required

Full

scored report every run

Every

question type included

5 free assessments a month · No card required · Pro from $16/mo

Overview

Most frontend hiring processes now put a skills assessment before the first real conversation. It is rarely a quiz about framework trivia — it is a scoped build or debugging task designed to show whether you can produce working, maintainable UI under time pressure. This page covers what those assessments actually contain, how they are scored, and how to prepare so the first one you sit is not the one that counts.

Why employers assess this role

Frontend is a field where résumés and reality diverge sharply. Two candidates can both list React and TypeScript, and one can ship an accessible, state-correct component in forty minutes while the other cannot get past the wiring. Employers assess because the gap is expensive to discover during a probation period, and because portfolio work cannot be attributed with confidence.

What gets tested

Component design and compositionState management and data flowAsync handling — loading, error and empty statesCSS layout, responsiveness and cross-browser behaviourAccessibility fundamentals (semantics, keyboard, focus)Debugging an unfamiliar codebaseReading a spec and asking the right clarifying questions

The format

Duration

45–90 minutes

Question types

Scoped build task (a component or small feature)
Debug an existing broken component
Code reading and explanation
Short written reasoning about trade-offs

Levels

Entry · Mid · Senior

What you'll be asked to do

Build a component from a spec

The most common format. You are given a short spec, sometimes a design, and asked to build a working component. The spec is usually slightly under-specified on purpose to see what you do about the gaps.

•Build a searchable, paginated list that fetches from a provided endpoint
•Implement a multi-step form with validation and a review step
•Build an accessible modal that traps focus and restores it on close

Handle real-world state

Assessors look hard at what happens outside the happy path — the loading state, the empty state, the failed request, the double-click on submit.

•Add optimistic updates to a list, with rollback on failure
•Prevent a duplicate submission while a request is in flight
•Show a meaningful empty state that distinguishes "no results" from "not loaded yet"

Debug something you did not write

A component with a specific defect — a stale closure, a missing dependency, an incorrect key, a layout that collapses at a breakpoint. You are scored on how you narrow it down, not just whether you fix it.

•A list re-renders on every keystroke; find and fix the cause
•A useEffect fires twice and duplicates a request
•A flex layout overflows its container below 768px

Explain your trade-offs

Often a short written section. Employers use it to separate people who made a considered choice from people who reached for the first thing that worked.

•Why did you put this state in a context rather than lifting it?
•What would you change if this list had 50,000 rows?
•What did you deliberately not build, and why?

Cohesyve for candidates

Practise a Frontend Developer assessment before the real one

Run the same AI job simulations companies use to evaluate applicants. You get a scored report showing where you're strong and where you're not, plus what to work on.

Sample tasks — and what strong looks like

Build a typeahead search input that queries an API as the user types and displays results below the field.

Mid

What strong looks like: Debounces or throttles input, cancels or ignores stale responses so results cannot arrive out of order, handles the empty and error states, and is keyboard navigable with correct ARIA roles. Weak submissions fire a request per keystroke and render whichever response lands last.

A provided component re-fetches data on every render. Find the cause and fix it.

Entry

What strong looks like: Reads the code before changing it, identifies the unstable dependency (usually an inline object or function in a dependency array), fixes the root cause rather than suppressing the lint rule, and can explain why the reference changed.

Given a design at one breakpoint, implement it so it works from 320px to 1920px.

Entry

What strong looks like: Uses intrinsic sizing and modern layout rather than a stack of fixed breakpoints, keeps tap targets usable on mobile, and handles long content gracefully instead of assuming the sample text.

Refactor a 300-line component into something you would be comfortable maintaining, and justify the boundaries you drew.

Senior

What strong looks like: Splits along genuine responsibility lines rather than by line count, extracts logic into hooks where it is reused, and gives a reason for each boundary. Weak answers create many tiny components with no clear ownership.

How to prepare

#1
Practise under a real timer. Most people who fail these tasks are competent but slow, and only discover it during the actual assessment.
#2
Rehearse the unhappy paths specifically — loading, error, empty, and double-submit. They are the most commonly skipped and the most heavily scored.
#3
Get comfortable reading unfamiliar code quickly. Debugging tasks reward navigation skill more than framework depth.
#4
Learn the accessibility basics that come up repeatedly: semantic elements, labels, focus management, and keyboard operation.
#5
Write a sentence explaining each non-obvious decision as you go. Many assessments award marks for reasoning, and it costs almost nothing.
#6
Do a full mock run end to end rather than isolated exercises. The failure mode is usually pacing, not knowledge.

Common mistakes

Spending most of the time on styling and running out before the functionality works.
Ignoring the error and empty states entirely, which is one of the fastest ways to lose points.
Silently guessing at an ambiguous requirement instead of stating the assumption.
Leaving console errors and warnings in the submission.
Over-engineering — adding a state library, an abstraction layer, or a design system for a forty-minute task.
Submitting without running it once from a clean state.

How it's scored

Criterion	What strong looks like
Does it work	The stated requirements function, including the edge cases named in the spec. This is weighted more heavily than anything else and is where most failures happen.
Code quality	Readable naming, sensible component boundaries, no dead code, and no copy-pasted blocks that should have been a function.
Handling of edge cases	Loading, error, empty and concurrent-action states are all considered, even if only briefly.
Accessibility	Semantic markup, operable by keyboard, labels on interactive elements. Rarely requires an audit — usually just the basics done correctly.
Reasoning	Assumptions are stated, trade-offs are explained, and the candidate can say what they would do differently with more time.

Frequently Asked Questions

How long does a frontend assessment usually take?

Most are 45 to 90 minutes. Take-home versions are sometimes longer but usually come with an explicit time expectation — treat that as a scoring boundary rather than a suggestion, because assessors do notice a submission that clearly took four hours.

Do I need to finish everything to pass?

Usually not. A partially complete submission that works correctly and handles its edge cases generally scores better than a fully complete one that is buggy. If you run short, make what you have solid and say what you would do next.

Can I use documentation and my usual tooling?

Almost always yes for documentation, and normally yes for your own editor and its standard tooling. Assessments are meant to reflect the job. If AI assistance is restricted, it is stated explicitly — check before you start.

Which framework will I be tested in?

Usually the one the employer uses, and usually stated in advance. Some assessments are framework-agnostic and score the underlying reasoning instead, which is why fundamentals travel further than framework-specific tricks.

How do I practise if I have never sat one?

Run a scored simulation before the real thing. Cohesyve gives you five free assessments a month with a full report, so you can find out where you actually lose marks while it costs you nothing.

Practise another role

Cohesyve · Practice for candidates

Practise a Frontend Developer assessment now — free.

Five scored assessments a month, a full report on every run, and a learning pathway built from what you got wrong. No card required.