Calculator skills for IGCSE Maths

Every calculator skill the exam expects, one page each: the exact keystrokes for the Casio ClassWiz (fx-991EX and fx-991CW), then the fx-CG50, TI-84 Plus CE, TI-Nspire CX II, a worked example, the mistakes that cost marks, and the same idea in Desmos.

Calculators: Casio fx-991EX ClassWiz (the fixed ROM) · Casio fx-991CW ClassWiz (the fixed ROM) · Casio fx-CG50 (OS 3.80) · TI-84 Plus CE (OS 5.8.x) · TI-Nspire CX II (OS 6.x). Checked September 2026.

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We open every guide on the calculator you pick (saved to your account when you are signed in, or on this device).

Watch every key press on YouTube: fx-991EX · fx-CG50 · TI-84 Plus CE

Algebra and graphs

Calculus

Statistics

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  1. Question 1 of 5
  2. Question 2 of 5
  3. Question 3 of 5
  4. Question 4 of 5
  5. Question 5 of 5

5 quick questions from across IGCSE Maths. No sign-in needed.

Work out \((2.5 \times 10^{6}) \times (4 \times 10^{-2})\). Give your answer in standard form.
Choose your answer · keys 1–4

Before every exam

  1. Know which papers allow it. Edexcel 4MA1: A calculator may be used in all four papers. Cambridge 0580: No calculator on Papers 1 and 2; a scientific calculator is needed for Papers 3 and 4. Algebraic or graphic calculators are not allowed. Which calculator is allowed.
  2. Degrees, always. Neither 4MA1 nor 0580 uses radians, so a D or Deg on the screen is the first check before any trigonometry: how to check and change it.
  3. Keep the full value. Use Ans or a stored letter instead of retyping a rounded number, then round the final answer to the accuracy asked for (3 significant figures on 0580 unless the question says otherwise).
  4. Fractions and surds. S⇔D switches between an exact answer and a decimal on the ClassWiz. Write the exact form when a question asks for a fraction or a surd: the key on other calculators.
  5. A table before a graph. "Complete the table" and "draw the graph" questions go faster with the calculator's table mode, and it shows where a root lies.
  6. A clean memory. The Cambridge Handbook says candidates must clear any information and programs stored in the calculator's memory before and after the exam. On a ClassWiz that is Initialize All. How to reset.

The exam-day checklist (print it with a free account) · Which calculators are allowed

Got an error message? Calculator error messages explained: what each one means and how to fix it.

New to these? Read the six calculator skills that cost the most marks, with the slips to avoid.

Diagram of the Casio fx-CG50's most-used keys: F1 to F6 under the screen, then SHIFT, OPTN, VARS, MENU, ALPHA, EXIT, the arrow pad and EXE
The fx-CG50 keys these guides use most (our schematic, not to scale). F1–F6 do whatever the bottom row of the screen says.

What you're allowed in the exam

Pearson Edexcel International GCSE Maths A (4MA1): the specification expects a suitable calculator in every paper (1F/2F and 1H/2H). It bans calculators with databanks, retrieval of text or formulae, a QWERTY keyboard, built-in symbolic algebra, or symbolic differentiation or integration. A scientific calculator such as the Casio ClassWiz (fx-991EX, fx-991CW) is the safe choice. Cambridge IGCSE 0580 is different: Papers 1 and 2 are non-calculator, and the syllabus says candidates should have a scientific calculator for Papers 3 and 4. Before taking a graphic calculator into either exam, check with your exams officer.

Which calculator for IGCSE Maths?

A Casio ClassWiz scientific calculator (fx-991EX, or the newer fx-991CW) suits both Edexcel 4MA1 and Cambridge 0580, and every guide here starts with it (graphs are done with a table of values, as the guides show). The 4MA1 specification bans calculators with databanks, retrieval of text or formulae, a QWERTY keyboard or built-in symbolic algebra (CAS). If you want to use a graphic calculator (fx-CG50, TI-84 Plus CE), check with your exams officer first. The guides here carry on with them for IB and A Level.

Sitting Cambridge IGCSE 0580? The syllabus says you should have a scientific calculator for Papers 3 and 4, and Papers 1 and 2 are non-calculator: practise the written methods with our 0580 non-calculator guide.

Which IGCSE topic each skill is for

The specification section (Edexcel 4MA1) and syllabus sub-topic (Cambridge 0580) where each calculator skill is first used. On 0580, use them on Papers 3 and 4 only. Teachers: a suggested teaching order.

SkillEdexcel 4MA1Cambridge 0580
Standard form and rounding1.9 Standard formC1.8 / E1.8 Standard form
Tables of values3.3 GraphsC2.10 / E2.10 Graphs of functions
Solving equations2.6 Simultaneous linear equationsC2.5 / E2.5 Equations
Quadratic graphs: roots and vertex2.7 Quadratic equationsC2.10 / E2.10 Graphs of functions
Graphs: intersections, zeros, max and min3.3 GraphsC2.10 / E2.10 Graphs of functions
Trig graphs and angle mode3.3 Graphs (Higher)E6.4 Trigonometric functions (Extended)
Sequences and sums3.1 Sequences (Higher)E2.7 Sequences (Extended)
Numerical derivative and integral3.4 Calculus (Higher)E2.12 Differentiation (Extended)
1-variable and 2-variable statistics6.2 Statistical measuresC9.3 / E9.3 Averages and measures of spread

For teachers

Every guide has a Show on the board view (big type, just the steps for the calculator you pick) and a printable one-page keystroke card with a QR code back to the guide. Tick the calculators your class uses on the class page (Settings tab), and your students' guides open on that calculator. For a suggested order by course, see Teaching GDC skills.

What about Desmos?

Desmos is not allowed in IGCSE exams. Use it to learn, to check an answer and to see the graph behind a question. Every guide ends with a "Do it in Desmos" section: the steps, and exactly what to type into the free desmos.com/calculator .

Questions

Is a calculator allowed in the exam?

Pearson Edexcel International GCSE Maths A (4MA1): the specification expects a suitable calculator in every paper (1F/2F and 1H/2H). It bans calculators with databanks, retrieval of text or formulae, a QWERTY keyboard, built-in symbolic algebra, or symbolic differentiation or integration. A scientific calculator such as the Casio ClassWiz (fx-991EX, fx-991CW) is the safe choice. Cambridge IGCSE 0580 is different: Papers 1 and 2 are non-calculator, and the syllabus says candidates should have a scientific calculator for Papers 3 and 4. Before taking a graphic calculator into either exam, check with your exams officer.

Which calculators do these guides cover?

Every guide has the keystrokes for: Casio fx-991EX ClassWiz (the fixed ROM) · Casio fx-991CW ClassWiz (the fixed ROM) · Casio fx-CG50 (OS 3.80) · TI-84 Plus CE (OS 5.8.x) · TI-Nspire CX II (OS 6.x). Each one ends with the same idea in Desmos, so you can check an answer.

What should I set before the exam?

Check the angle mode (radians or degrees), clear old list data, use Ans and stored values instead of retyping rounded numbers, and practise once in exam mode so nothing surprises you on the day.

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Sources

Keystrokes follow the manufacturers' manuals for the OS versions shown and were cross-checked against published teaching guides. Where a manual was ambiguous we say so on the page instead of guessing.