Does HackerRank Detect AI or ChatGPT?

HackerRank is where a lot of CS students take their first online assessment for an internship, so it is reasonable to wonder what it can see. The short answer is yes: HackerRank documents a feature built to flag AI-assisted cheating in coding questions. But it works by looking at how you produced your answer, not only at the final code, and it produces a flag for a human to review rather than a verdict. Everything below comes from HackerRank's official help center articles, which we read in October 2026. Features change, so check the linked pages for the current version.

Which HackerRank this is about

HackerRank has a public practice site and a separate product that companies use to run hiring tests. The help center articles cited here describe the hiring product: tests that a company sends you, with settings the company controls. We did not find official documentation describing AI detection on the public practice problems, so this page does not make claims about them.

AI Plagiarism Detection

HackerRank's AI Plagiarism Detection article says the feature targets three kinds of code plagiarism: use of AI tools when explicitly prohibited, copying from other external sources like the internet, and copying from someone else who took the same test.

It is described as a machine learning model that looks at several signals together, including:

• code writing patterns,
• time taken to solve the problem,
• copy-paste activity, and
• tab-switching behavior.

The model sorts suspicious attempts into "High" or "Medium", which the article says reflect its confidence. Reviewers can open a keystroke playback of the attempt to see where the suspicious activity happened.

The same article is open about the limits:

• It supports coding questions only.
• It is limited on questions that need minimal effort for a full score, or where the solution is only a few lines long.
• It needs copy-paste tracking and tab proctoring to be enabled.
• Candidates must consent before starting a test that has it enabled.
• The model has an overall precision of 85 percent, which HackerRank explains as flagged sessions being correct 85 percent of the time, and the article says human oversight remains crucial.

That precision figure is HackerRank's own number. Read the other way, it means about 15 percent of flagged sessions are not correct, which is why a person is supposed to look before anything is decided.

MOSS similarity checks

Separately, HackerRank's MOSS article says it runs MOSS (Measure Of Software Similarity) on tests by default. MOSS turns code into tokens and compares them with other submissions, so renaming variables or changing whitespace does not hide a copy. The article sorts matches into High (90% or more), Medium (80% to 90%) and Low (under 80%), says MOSS cannot determine the exact source of plagiarism, and recommends reviewing the code playback before making a final decision.

MOSS on its own finds similarity, not AI. Our page on whether MOSS detects AI code explains why that distinction matters.

Proctor Mode

HackerRank's Proctor Mode article describes an AI-powered feature that simulates live human proctoring. According to that page, it monitors whether the candidate is present via webcam, captures screenshots during the test, takes them more often after suspicious activity such as switching windows, and can analyze the screenshots. The company has to enable it at both the company level and the test level, so not every test uses it.

Some tests allow AI

HackerRank's AI features page also lists an AI Assistant that can be available inside a test, with modes ranging from code completion and debugging help to more open chat and agent-style help. In other words, some employers want to see how you work with AI. Whether AI is allowed is decided by the company that sent the test, not by HackerRank in general. If the instructions do not say AI is allowed, treat it as not allowed, and ask the recruiter if anything is unclear.

What this means if you are taking a test

• Read the test's rules and consent screens. They tell you which monitoring is on and what help is permitted.
• A flag is not a finding. HackerRank's own articles describe flags as something a reviewer should check, and they admit some are wrong.
• Normal habits can look odd out of context. Pasting a snippet you wrote in another window or switching tabs to read docs may be recorded. If something like that happened, it is better to mention it to the recruiter than to hope nobody notices.
• Your real protection is understanding your answer. Many companies follow an online test with a live interview where you explain or extend your code. Work you cannot explain will not survive that, whatever a tool said.

Checking how your code reads

You cannot run HackerRank's model yourself, and it uses signals like typing and timing that a pasted file does not contain. What you can do, when practicing outside a test, is see whether your code has the style patterns people associate with AI output. Paste it into the detector at the top of this page and read the reasons it lists. If it points to things you would not normally write, that is a good prompt to make sure you can explain every line. For the general signs reviewers look for, see how to tell if code was written by ChatGPT.

Read more

• My code was flagged as AI but I wrote it — steps to take if a tool flags your work.
• Does MOSS detect AI-generated code? — how similarity checking works.
• Can professors tell if you used ChatGPT for code? — the checks courses use.

Frequently asked questions

Try the detector

Have a snippet you are unsure about? Paste it into the free AI Code Detector to get a verdict, an AI probability and the reasons behind it. No sign-up, and your code is not stored.