A diagrammatic reasoning test shows you boxes, arrows and shapes and asks what comes out at the end. There are no words to read and no numbers to calculate. What it measures is whether you can work out a rule from a few examples and then apply it, step by step, without losing track. The format feels strange the first time you see it, and that unfamiliarity is the part practice fixes most directly.
This guide explains the question formats, works through two illustrative examples, and sets out a practice routine. For the wider family of aptitude tests (verbal, numerical, how scores are used and the legal points around adjustments), see our separate guide to cognitive ability tests; here the focus is on diagrams only.
What the test is measuring
Saville Assessment, one of the test publishers, describes its diagrammatic test as assessing “the ability to analyze diagrams, sequences and transformations”. That is a useful working definition. You are not being tested on knowledge. You are being tested on three linked skills:
- Rule discovery: looking at a few examples and inferring what each symbol or step does.
- Rule application: using the rules you found on a new input, in the correct order.
- Working memory: holding an intermediate result in your head while you apply the next step.
The University of Manchester careers service notes that logical and diagrammatic tests are more popular for IT and engineering positions. That fits the content: tracing an input through a sequence of operations is close to reading code, a wiring diagram or a process flow. Test Partnership, another publisher, makes the point that the labels “diagrammatic”, “abstract” and “inductive” mostly reflect the publisher’s choice of format; the core task is identifying a logical rule and applying it consistently.
The three formats you are likely to see
| Format | What is on screen | What you must do |
|---|---|---|
| Flowchart or operator | A shape enters at the top, passes through boxes with symbols, and exits at the bottom | Work out what each symbol does from the examples, then predict the output for a new input, or identify which symbol is missing |
| Next in series | A row of diagrams that change from one to the next | Find the change rule and pick the diagram that comes next |
| Rule grouping | Two sets of diagrams, each sharing a hidden rule | Decide which set a new diagram belongs to, or whether it fits neither |
The flowchart format is the one most people mean by “diagrammatic”. Test Partnership notes that some SHL diagrammatic items use this style, where a shape passes through operators that do things such as rotate, flip or resize it. Next-in-series questions also appear inside broader tests; Oxford’s careers service describes SHL’s non-interactive general ability test using a row of diagrams labelled A to E and asking which comes next.
How long you get
Timing depends on the publisher and the version, so read the invitation. As one example, Saville’s published technical summary lists its full diagrammatic reasoning test at 32 questions in 16 minutes, roughly 30 seconds per question. The same document lists a shorter diagrammatic section inside its combined technical aptitude test: 8 questions in 4 minutes. Other publishers use different lengths and some tests are adaptive, so treat these numbers as an illustration of the pace, not a rule for every test.
The practical lesson is that you cannot afford to rediscover what each operator means on every question. You need a method that lets you decode the operators once and reuse them.
Worked example 1: decoding operators (illustrative)
This is an invented question written for this guide. It shows the logic, not any publisher’s real item.
You are shown three example routes. Each route passes a shape through two or three operator boxes.
- A black square goes through box # and comes out a white square.
- A white triangle pointing up goes through box @ and comes out a white triangle pointing down.
- A black triangle pointing up goes through #, then @, then %, and comes out as two white triangles pointing down.
Question: a white circle goes through %, then #. What comes out?
Method. Start with the routes that use the fewest operators, because they give you clean evidence.
- Route 1 has one operator. Black became white and nothing else changed, so # reverses the colour.
- Route 2 has one operator. The triangle flipped vertically and kept its colour, so @ flips the shape top to bottom.
- Route 3 combines all three. After # the triangle is white and pointing up; after @ it is white and pointing down. The final output is two of them, so % duplicates the shape.
Now apply the rules in order to the new input. A white circle duplicated by % becomes two white circles; # reverses the colour, giving two black circles.
Notice what made this fast: writing a one-word label next to each operator (“colour”, “flip”, “double”) as soon as you decoded it. With that note, the final step takes seconds.
Worked example 2: when the order matters (illustrative)
Some operators interact. Suppose you decode & as “rotate 90 degrees clockwise” and ! as “add a dot in the top-left corner”. An arrow pointing right that passes through ! then & ends up pointing down, and the dot has moved with the shape to the top-right. Pass the same arrow through & then ! and it still points down, but the dot sits in the top-left, because it was added after the rotation.
This is the kind of distinction the hardest questions test. When two answer options differ only in where a detail sits, ask yourself which operator came last.
A five-step method for flowchart questions
- Scan the examples for single-operator routes. They decode one symbol each with no ambiguity.
- Change one attribute at a time. Check colour, then size, then orientation, then number, then position. Most operators change one property.
- Label each operator in a word. Use rough paper if it is allowed. If not, say the label under your breath.
- Use multi-operator routes to confirm, not to discover. Once you think you know two operators, a three-operator route tells you the third.
- Eliminate answers before computing. If the correct output must be black, discard every white option first. Often one or two options remain.
Mistakes that cost the most marks
| What happens | Why | Fix |
|---|---|---|
| You pick an answer that is right except for one detail | Applied operators in the wrong order | Trace the route from top to bottom every time, even when you think you know the answer |
| You run out of time with half the questions left | Re-decoding operators on each question | Note each operator’s meaning once; many tests reuse the same set across several items |
| Two rules both seem to fit | Hypothesis formed from a multi-operator route | Go back to the simplest route; it usually rules one out |
| You freeze on an unfamiliar symbol | Expecting the symbol itself to mean something | Symbols are arbitrary; only their effect on the shape matters |
| Strong start, weak finish | Fatigue and lost concentration | Practise at full length, under time, at least twice before the real test |
A practice routine that works
Manchester’s careers service gives advice that applies directly: practise to improve your response times and confidence, work quickly because assessors look at both speed and accuracy, and practise with tests from the same supplier you will sit if you can. Ask the employer which publisher it uses, or check the invitation email; publishers usually name themselves on the test platform.
A sensible routine over two weeks:
- Sessions 1 and 2, untimed: do 15 to 20 questions slowly. After each one, write down which attribute every operator changed. The aim is to build a mental list of common operator types.
- Sessions 3 and 4, loosely timed: allow about a minute per question. Check every wrong answer and classify the error using the table above.
- Sessions 5 and 6, real pace: full-length practice at the time limit stated for your test. Saville says practice tests with feedback and realistic time limits are available for its tests; other publishers offer similar material.
- The day before: one short timed set to warm up, then stop. Cramming abstract puzzles late at night tends to make you slower, not faster.
On the day, use a laptop or desktop with a reliable connection, close notifications, and have rough paper and a pen if the instructions allow it.
Where the test fits in the hiring process
Online reasoning tests are usually an early filter, sent soon after you apply. Publishers supply comparison groups (Saville, for instance, offers international and country-specific norms), so your score is often read against how other people performed rather than as a raw mark, and it is one piece of evidence alongside your application and interviews. Your CV still has to get you invited in the first place, so it is worth making sure it shows the analytical and technical work that made you a fit for the role. If you are applying for engineering or IT roles, an online resume builder with ATS-friendly templates can help you present that evidence clearly, and our answers to common resume questions cover what employers screen for before any test is sent.
Frequently asked questions
Is a diagrammatic reasoning test the same as an abstract reasoning test?
They overlap. Both ask you to find a rule in shapes or symbols and apply it. Test publishers use different labels, and diagrammatic tests more often use the flowchart format, where a shape passes through a series of operators.
Do I need maths for a diagrammatic reasoning test?
Usually not beyond counting. The work is spotting and applying rules such as rotation, reflection, adding or removing elements, and changing colour or size. Numerical tests are a separate assessment.
What if I do not finish all the questions?
Many people do not. Tests are timed and scored on both speed and accuracy, so keep moving and avoid spending minutes on one item. Check the instructions for whether wrong answers are penalised; if the employer or publisher says nothing, ask.
Can I ask for extra time?
If you have a disability or condition that affects timed tests, contact the employer before you start and ask what adjustments are available. Do this early, because the link often has a deadline.
Sources
- Diagrammatic, Spatial and Mechanical Aptitude: Technical Aptitude Range Technical Summary (Saville Assessment)
- Reasoning tests: numerical, verbal, logical, diagrammatical (University of Manchester Careers Service)
- Mastering the SHL Tests: The Complete Guide (University of Oxford Careers Service)
- Diagrammatic reasoning (Test Partnership)