HackerRank is a platform that companies use to build their own coding tests, which is why two "HackerRank tests" can look nothing alike. Amazon, for example, runs the coding round of its SDE II assessment on it. What doesn't change from company to company is how the platform works and how it scores you, and that is what this guide covers, from HackerRank's own candidate documentation.
What you might be asked to do
Each employer picks from HackerRank's question types:
- Coding, the core of most tests.
- Multiple choice and SQL queries.
- Projects: front-end, back-end, full-stack and mobile.
- Data science in Jupyter notebooks, DevOps and cloud tasks.
- Code review, diagrams or whiteboard questions, and written answers.
Your login page shows the time limit and the list of questions before you start, so read it carefully.
How coding answers are scored
Coding answers are run against test cases automatically:
- Partial credit: you get marks for each test case you pass, so a solution that handles most cases is worth a lot more than nothing.
- Hidden test cases: some cases aren't shown to you, and they often carry points. They often test edge cases.
- Exact output: your output must match the expected format exactly. An extra space or line break can fail a correct solution.
- Time's up: when the timer runs out, your last compiled code is submitted automatically.
Cohesyve
Practise this before it counts
Run the same kind of AI job simulation employers use and get a scored report on where you stand. 5 free assessments a month, no card required.
The rules
HackerRank treats these as malpractice: copying code, getting outside help, leaving full-screen and switching tabs. Plagiarism flags are shown to the employer, not to you.
Some employers switch on HackerRank's AI assistant. In "guarded" mode it gives hints and syntax help but not full solutions; in "unguarded" mode it works like an AI coding agent. Using it doesn't change your score, but it is logged for whoever reviews your test. If the assistant isn't switched on, assume AI help isn't allowed.
Before you start
HackerRank's own advice to candidates:
- Take the sample test first to learn the editor.
- Use a PC or laptop. Phones and tablets aren't supported.
- Use an up-to-date browser: Chrome, Firefox, Edge or Safari.
- Have a webcam ready if the test is proctored; your invitation will say.
- The timer can't be paused, so start only when you have the whole time free.
- In Java, C# and Scala, name your main class Solution.
Results and retakes
The employer owns your report. HackerRank doesn't send you your results and can't reactivate an expired test link. Whether you can retake a test is up to the employer, so contact them, not HackerRank.
How to prepare
Learn the editor before it matters. The sample test shows you how input is read and output is printed. Points are often lost to formatting rather than logic.
Write for the hidden cases. Before you submit, think about empty input, a single item, duplicates, very large numbers and negative values. Hidden tests often cover them.
Bank partial credit. If a full solution is out of reach, a correct simple version that passes most cases is worth submitting first. Then improve it.
Compile early and often. Since your last compiled code is what gets submitted when time runs out, keep a working version compiled at all times.
Practise the question types you'll get. If the job is front-end, practise a small project, not just algorithm puzzles. The invitation or the recruiter can usually tell you what to expect.
Where Cohesyve fits
Coding tests check that you can write correct code under time pressure. Many teams then look for how you handle work closer to the job: debugging code you didn't write, reviewing a change, explaining a decision. Cohesyve, which publishes this guide, runs practice job simulations for that kind of stage, with a report on where you lost marks. It isn't a HackerRank practice test.
Sources
Checked 2 October 2026.