Which Calculator Do I Need for A Level Maths?

Every September I see students start Year 12 with the calculator they used at GCSE. Most of them find out within a couple of weeks that it won't do what the course needs. Some go months longer, working things out the long way round, before anyone tells them that a lot of what they're finding slow is meant to take one button.

This is what I think you need, what I'd buy, and the one question worth asking before you spend anything.

The short answer

Check with your school before you buy anything

Best overall

Casio fx-CG100

The current Casio graphical calculator, and worth it if you will learn to use it.

Around £100

Science Studio

Best value

Casio fx-991CW+

Everything A Level asks of a scientific calculator, for a quarter of the price.

£25 to £30

Science Studio

Best second hand

Casio fx-CG50

Discontinued but still exam approved, and the model most UK tutorials were written for.

Around £100

Science Studio

In this guide

• Ask your school first
• What the exam boards require
• Why a GCSE calculator is not enough
• Our pick: the Casio fx-CG100
• Is a graphical calculator worth it?
• The scientific choice: fx-991CW+
• The other graphical option
• NumWorks: the wildcard
• What about the fx-991EX?
• If you take Further Maths
• The rules on exam day
• Every model compared

Before you buy anything, ask your school

Most schools and colleges recommend a particular calculator, and there's a good reason for it. Teaching a class is much easier when everyone has the same model. The teacher can put the key presses on the board, students can help each other, and nobody spends half the lesson looking for a menu that's somewhere else on their calculator.

If you turn up with a model nobody in the department has used, you'll be working it out on your own the first time you can't find a function. That's time you could have spent on the maths.

What the exam boards require

Edexcel, AQA and OCR all set the same practical minimum for A Level Maths. Your calculator has to be able to:

• Handle an iterative procedure, so you can repeat a calculation using the previous answer.
• Compute summary statistics from a data set, such as the mean and standard deviation.
• Give you probabilities from the binomial and normal distributions, including the cumulative versions.

There's also a limit at the top end. Calculators that do symbolic algebra or symbolic calculus, usually called CAS models, aren't allowed in any A Level Maths exam. If it shows you the algebraic steps of a solution, it can't be used. Graphical calculators without that feature are allowed in every A Level Maths and Further Maths paper.

Why a GCSE calculator isn't enough

It's tempting to read that list, see the word statistics, and assume your old calculator will do until the statistics comes up. It won't, and most students find that out a lot sooner.

The usual GCSE calculators, the Casio fx-83 and fx-85 families, are built for a different course. They're fine for basic calculations, but they can't do most of the things that save time at A Level:

• Solve an equation. There's no quadratic or cubic solver, so checking the roots of a quadratic has to be done by hand every time. That starts in the first few weeks of Year 12.
• Solve simultaneous equations, which come up everywhere from coordinate geometry to mechanics.
• Evaluate a definite integral or a gradient numerically, which is the quickest way to check your calculus.
• Give you the binomial and normal distributions, the requirement above. This is where the calculator goes from being slow to not being usable at all.

That isn't a criticism of those calculators. They do what they were designed for, but A Level asks for more, and early on.

It's also worth sorting this out now rather than at Christmas. The sooner you have the calculator, the longer you have to get used to it. That matters most if you go graphical, because it'll feel quite different to the one you used at GCSE, and it usually takes a few weeks before you stop searching through menus.

Our pick: the Casio fx-CG100

If you can afford it, and you're willing to learn how to use it, the Casio fx-CG100 is the calculator I'd suggest for most A Level students. It's Casio's current top of the range graphical calculator for UK schools, it's approved for A Level and Further Maths, and it replaces the model most sixth forms have used for years.

That model was the fx-CG50, which has now been discontinued. Casio stopped making it and expected the last stock to sell out during autumn 2025, with the classroom emulator being retired during the 2026 to 2027 academic year. Existing CG50s are still allowed in exams and are still good calculators, but if you're buying new, it's a model on the way out.

The obvious downside is the price. Graphical calculators are around £100, compared with under £30 for a scientific one, so it's worth being honest with yourself about whether you'll use it enough to justify that.

Is a graphical calculator worth it for you?

A graphical calculator is only worth buying if you are willing to learn how to use it.

If you sit the exam with a £100 calculator you only know how to use as a scientific one, you've paid a lot for nothing extra, and you may lose time looking through menus under pressure. If you don't think you'll put the time in during Year 12, I'd buy a good scientific calculator instead.

For most of the course it makes very little difference which calculator you have. Differentiation, integration by parts, trigonometric identities, proof, vectors and most of mechanics are the same whichever one you're using.

Where a graphical calculator does help:

• Critical regions in hypothesis testing. A graphical calculator has an inverse binomial function, so you can go straight from a probability to the boundary value. A scientific calculator only gives you cumulative probabilities, so you have to try values one at a time until you find the boundary. This is the clearest case where the better calculator saves time in an exam.
• Seeing the graph. This helps right through the functions work. Roots, intersections, turning points, asymptotes and transformations are much easier to think about when you can see the curve rather than imagine it. It's also a quick check, because if your algebra gives three roots and the screen shows one, you know to go back and look again.
• Equation solving. Polynomials, simultaneous equations and numerical solutions, more quickly and for more cases.

If you're going scientific: the fx-991CW+

This is where most students end up, and it's a perfectly good choice. If you've decided against a graphical calculator, you still need one that meets the requirements above. The standard choice for A Level Maths is the Casio fx-991CW, and there's now a revised version, the fx-991CW+, which is the one I'd look for.

The original CW came with a redesigned menu system that not everyone liked. The most common complaint was that switching between fractions and decimals, which you do all the time, took more presses than before. The CW+ sorts out several of those points.

Either version will do the job, and both are approved for GCSE and A Level. If the CW+ is available where you're buying, I'd get that one.

The other graphical option

If the CG100 is over your budget, or you find a good price on the model it replaced, the fx-CG50 does the same job.

NumWorks: the wildcard

Almost everyone in a UK sixth form uses a Casio. NumWorks is the exception worth knowing about, and it's a good calculator in its own right. Judged on its own, I think it does most things better than the Casios, and more intuitively. The menus are in plain words, the screen is colour, Python is built in, and most people can find their way round it without the manual. It feels like a more modern design.

It's also allowed in your exams. NumWorks meets the JCQ requirements, and the calculator has a UK exam mode. Switching it on clears the memory, removes any programs or applications you've added, disables the Elements app, and shows a marker on the screen for the whole paper. Turning it on before an exam is the sensible thing to do, and it's what makes the calculator straightforwardly compliant.

The drawback is that very few people around you will know how to use it.

What about the fx-991EX?

For years the fx-991EX was the scientific calculator most students had, and plenty of teachers and students still prefer it. If you already have one, from GCSE or handed down from an older brother or sister, keep using it. It's sturdy, quick, well laid out, and it does everything A Level Maths requires.

Buying one now is different. It's been replaced, so genuine new stock is hard to find, and a lot of what's sold cheaply on online marketplaces is counterfeit. That matters more than it might sound, because counterfeit units have been reported to give incorrect results on calculations, which isn't something you want in an exam.

If you're taking Further Maths

Everything above assumes A Level Maths on its own. If you're also taking Further Maths, the case for a graphical calculator is stronger.

A lot of Further Maths is easier to follow when you can see it. Polar curves and parametric equations are the clearest example. A graphical calculator plots both, and a scientific calculator can't plot anything. Complex numbers, matrices and vectors are also easier on the graphical models, and being able to check an inverse, a determinant or a cross product quickly is useful when the algebra gets long.

It isn't essential, and plenty of students do Further Maths with a good scientific calculator. But if you're undecided about spending the extra, Further Maths is probably what tips it.

The rules on exam day

Whatever you buy, the regulations make it your responsibility rather than the school's. Before every paper you're expected to:

• Make sure the calculator works and the batteries are good. I'd change them before the exam season starts rather than on the morning.
• Clear the memory, including anything stored in variables or programs.
• Remove any case, lid or cover with printed instructions or formulae on it. A lot of calculators have exactly that on the back of the lid.

Calculators must also be quiet, hand held and self powered, and must not hold retrievable information such as databanks or notes. Scientific constants are fine.

Every model compared

Check with your school first. If the choice is yours and the budget allows, I'd buy the fx-CG100 and commit to learning it. If not, or if you know you won't put the time in, buy the fx-991CW+ and get to know it well. In my experience a student who knows their scientific calculator inside out tends to do better than one who owns a graphical calculator but hasn't learnt to use it.

Whichever you choose, learn it in Year 12 rather than the week before your first paper. Like everything else at A Level, it comes down to practice.

Prices are a guide only and change. The buy links above go to Science Studio, an authorised Casio supplier who tends to be well under the big marketplaces on the same calculator. They're not the only option, and your school's own supplier is often cheaper again, so it's worth comparing before you order. We are not paid for any link on this page.

Photograph credits

• fx-CG100: photograph by Hikari K, CC0, cut out from the original.
• fx-CG50: photograph by Quinticdot, CC BY 4.0, cut out from the original.
• fx-991CW: photograph by AST14, CC BY-SA 4.0, cut out from the original.
• fx-991EX: photograph by Ruhan, CC BY 3.0, cut out from the original.
• NumWorks: photograph by Samename92, CC BY 4.0, cut out from the original.
• fx-83GT Plus: photograph by JohnGold6000, CC BY 4.0, cut out from the original.