Codility Test: What to Expect From Invitation to Report

A Codility Screen test starts with an intro page you can read without starting the clock, runs on a single timer that cannot be paused, and ends with a set of checks on your submission that you never see. As of September 9, 2026, Codility's candidate documentation covers each step, and the employer's choices about proctoring show up before you press Start. This walkthrough follows that order.

Step 1: Open the link, but do not press Start

Codility's candidate FAQ says you can open the invitation "to read introductory information, assessment policies from your testing team, and see how many problems (or 'tasks') you will be asked to solve and how much time you will have." The page adds: "Unless you press the 'Start' button, you can leave and come back when you are ready."

Read the policies section. Codility's rule for every test is that "you must work on your own," and whether books, websites, or your own editor are allowed is set by the employer's policies on that page, per the outside help FAQ. If proctoring is enabled, the same page carries a disclosure "informing them of the specific behaviors that will be visible to recruiters." How to read those tells is covered in whether your Codility test is proctored.

Step 2: Check the browser or install the app

For a browser test, Codility's software FAQ lists "Chrome ≥ 131, ChromiumEdge ≥ 130, Firefox ≥ 132, Opera ≥ 114, Safari ≥ 17" and says "You will not need to install any applications or browser plug-ins." If the test uses camera or screen features, use Chrome: the supported browsers page states "We currently only support Chrome for any recording and screenshooting related functionality," and phones and tablets are unsupported.

If the link shows a download page instead, the employer enabled Device Integrity and the test runs in the Codility App. The candidate app guide requires "A computer running macOS or Windows (Linux is not supported)" and permission to install software, and says the interface is "the same assessment or interview interface you'd see in a web browser." Linux users are told to "contact the company that invited you."

Step 3: Permission gates

Only proctored tests have this step. If snapshots or video are on, the camera FAQ says "You won't be able to start the test until you go through the process of initial setup for the camera." For screen sharing, you "can choose between sharing a tab, a window, or entire screen," and "candidates must select 'Allow' in order to proceed." Video Proctoring adds the microphone and shows "the recording indicator right next to the time remaining."

What each of those features captures is detailed in when Codility uses your webcam.

Step 4: The timer

Codility's time FAQ says tests "typically last between half an hour and two hours," that the limit shown "is for the whole assessment, not a single task," and that "once you begin the assessment, you cannot pause or stop the timer." When it expires, "the code present in the IDE is submitted automatically."

One reassurance from the same page: "the time it takes you to solve the tasks does not factor into automated scoring." Speed only matters as a proctoring signal, where "Abnormally short durations" can be flagged, and as the input to Typing Pattern Detection.

Step 5: Working in the IDE

You can run and test as often as you like before submitting. The task description cannot be copied from the IDE, and when proctoring is on, the attempt is logged. Paste is allowed and visible: the report guide shows a pink arrow for "Text pasted into the editor" on every report's timeline, alongside a light blue line for time "Out of focus." If the policy permits your own editor, the own-IDE FAQ says to "paste the solution back into the Codility interface" and use Run to confirm it compiles.

Step 6: After you submit

Three things happen without you. If you reach the passing score, or 40% with none set, Similarity Check compares your code against "over 12 million assessments" and against AI-generated solutions. Typing Pattern Detection, on by default, analyzes keystroke structure "after they submit their assessment." Network IP Detection checks whether the session came "from the same device or location." The results feed an Integrity Risk level of None, Low, Moderate, or High that Codility says is calculated with "No AI." All of it goes to the employer's report; Codility's fraud page says a flag "is not a guarantee that the candidate has cheated." The AI-specific layers are explained in whether Codility can detect ChatGPT.

An employer may also enable AI Follow-Up Questions: "three targeted questions unique to that submission," each "time-boxed to 2 minutes, with copy-paste prevention and keystroke monitoring active." Expect to explain your own solution in writing, on a clock.

Preparation checklist

1. Open the link a day early and read the policies and the task count.
2. Ask the test administrator, in writing, about anything the policies leave unclear.
3. Use Chrome on a laptop or desktop; install the Codility App if the link requires it.
4. Set aside the full time limit plus setup; the timer does not pause.
5. If a camera or screen prompt appears, tidy the room and the screen before clicking Allow.
6. Write in the Codility editor unless the policy permits your own, and be ready to explain every line.

The complete inventory of Codility's checks, including the ones that run on every test, is in what Codility detects.