Coding assessments

Assess coding knowledge, not just code

Test how developers really think — reading, debugging and reasoning about code — with structured questions that mark objectively and instantly, plus syntax-highlighted code anywhere and free-text code answers.

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Instant objective marking
Syntax highlighting
Structured code questions

Coding question · Single Best Answer

Marked instantly

def average(values):

total = 0

for v in values:

total += v

return total / len(vals)

Which option best explains why this function raises an error?

A
total is never initialised
B
You cannot divide by len(...)
✓
vals is not defined — it should be values
D
The loop variable v is out of scope

10 million+

exams delivered worldwide

Trusted by awarding bodies, universities & professional bodies

A better way to assess code

More than “write and run code”

Writing code from scratch is only one way to test a developer — and it’s slow to mark and hard to standardise. Reading, debugging and reasoning about code often reveals understanding more sharply, and it can be marked objectively and instantly.

Synap lets you build rigorous, structured coding questions around real code: spot the bug, predict the output, explain why it fails, complete the missing line. Fast for candidates, consistent to mark, and defensible at scale.

Explore standardised testing

Read & debug real code
Show candidates real, syntax-highlighted code and ask what’s wrong.
Predict the output
Test whether candidates can reason about what code actually does.
Explain why it fails
Ask candidates to identify the cause, not just the symptom.
Instant, objective marking
Structured questions are marked the moment they’re submitted.

The question toolkit

Coding questions, without a sandbox

Build coding assessments from the question types that mark objectively and instantly — no code execution required. Drop syntax-highlighted code into any question, then ask about it with single best answer, cloze and short-answer formats.

Syntax highlighting covers popular languages such as Python, JavaScript, Java and C++, so code reads exactly as it should.

Syntax-highlighted code anywhere
Add code blocks or inline code to any question, option or feedback.
Single best answer on code
“What is the output?”, “Why does this fail?” — marked instantly.
Cloze & drag-and-drop
Drag the correct statement into the gap, or fill it in.
Short answer, auto-marked
Accept typed answers matched against your accepted responses.

Coding question · Drag & drop

Auto-marked

Drag the correct statement to complete the swap:

for i in range(n - 1):

if arr[i] > arr[i + 1]:

arr[i], arr[i+1] = arr[i+1], arr[i]

Statements

arr[i], arr[i+1] = arr[i+1], arr[i]arr[i] = arr[i+1]swap = arr[i+1]

Writing code

Let candidates write code, too

When you do want candidates to write or fix code, Free Text answers let them type freely, with syntax-highlighted code blocks. Provide an answer template to pre-fill the box with starter code — ideal for “edit” or “fix this function” tasks.

For larger, real-world tasks, candidates can work in their own IDE and submit an entire project with a File Upload question — download a starter project, fix the bug, and re-upload it. Free-text and uploaded code are marked by your examiners, so you can apply rubrics and multiple marker roles.

Explore marking & grading

Free Text code answers
Candidates write code, with syntax-highlighted code blocks.
Answer templates
Pre-fill the answer with starter code to edit, fix or complete.
File upload for whole projects
Download a starter project, fix it, and re-upload the whole thing.
Rubric & examiner marking
Score written and uploaded code with rubrics and marker roles.

AI-resistant proctoring

Make sure it’s the candidate, not an AI

Coding assessments are a prime target for AI assistants. Synap’s proctored desktop app runs pre-flight checks before the exam starts — and if a prohibited application such as an AI coding assistant is running, the exam is blocked until it’s closed.

During the exam, whole-screen recording captures the candidate’s entire screen — their process, not just the final answer — alongside a locked-down environment and continuous monitoring. That’s also what lets you safely allow candidates to work in their own IDE for larger, project-based tasks.

Pre-flight application checks
Detects the applications running on the candidate’s machine before they begin.
Blocks prohibited apps
Stops AI assistants and remote-control tools from being open during the exam.
Whole-screen recording
Records the candidate’s entire screen, so you see how they worked — not just the answer.
Full-screen lockdown
A locked-down environment that limits switching away from the exam.

Explore proctoring

Synoptic · System check

Blocked

Camera and microphoneAccess granted
Screen sharingAccess granted
Full screenFull screen is on
Prohibited applications1 detected

remote-desktop.exe detected

The following applications have been detected running on your system. They must be closed before the exam can start.

Run check againStart exam

For modern engineering teams

Built to fit how software teams work

Teams that assess coding on Synap tend to reach for the rest of the platform, too.

See it in action

Assess coding knowledge, objectively and at scale

Book a tailored demo and we’ll show you how to build structured, instantly-marked coding questions on Synap.

Book a tailored demo

What our customers say

The platform structure (library items placed into collections) makes multiple course variations very easy, saving significant amounts of time. Easily the best learning platform I have worked with or interacted with as a student.
Fergal T
Data & Automation | Frasers
The features we like most about Synap are the spaced learning, mock exams, and the customer support we receive by the Synap team! When we want to make changes, they are always there to help us through the process.
Jonathan D
Driver Operations Executive | FreeNow
Synap came to our rescue when we needed a platform for computer-based testing, with a short turnaround time. Readily customizable, easy to use. We are very impressed with Synap and hope to continue working with them for our annual testing needs.
Lauren N
Chair | AAO

FAQs

Coding assessment questions, answered

Find quick answers or browse our academy.

Still not sure?

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Or ask an AI about Synap

Does Synap run or execute candidate code?

No — Synap doesn’t compile or execute code, and there’s no built-in code sandbox. Instead you assess coding knowledge with structured questions (spot the bug, predict the output, explain the error, complete the line) that mark objectively and instantly, plus free-text answers for writing code that your examiners mark. Many teams find this a faster, more standardised way to screen understanding.

How do you assess coding without running code?

By testing understanding directly. Drop syntax-highlighted code into a question, then ask about it with single best answer, cloze/drag-and-drop or short-answer formats — “what is the output?”, “which line causes the error?”, “drag the correct statement into place”. These are marked the moment they’re submitted.

Can candidates write code?

Yes. Free Text answers let candidates write or edit code with syntax-highlighted code blocks, and you can provide an answer template that pre-fills the box with starter code for “fix this function” tasks. Free-text code is marked by your examiners, so you can apply rubrics and multiple marker roles.

Which languages are supported for syntax highlighting?

Popular languages including Python, JavaScript, Java, C++, C#, Ruby, PHP, TypeScript and more, with syntax highlighting applied automatically to code blocks so code is easy to read.

Are coding questions marked automatically?

Structured questions — single best answer, multiple correct, cloze/drag-and-drop and short answer — are auto-marked objectively and instantly. Free-text code answers are marked by an examiner, which is where rubrics and marker roles come in.

Who uses Synap for coding assessments?

Software companies and training providers on modern tech stacks — for certification, course assessment and hiring screens. They typically combine coding questions with our APIs and integrations, on-demand exams and proctoring.