Choosing your IB HL subjects: what actually matters
8 September 2026 7 min read
HL choices get made in a fog of secondhand advice, usually from students a year above who are themselves guessing. Some of it matters a great deal and some of it is folklore, and the two are hard to tell apart when you are fifteen.
Here is what genuinely constrains the decision, and what does not.
Course requirements are the only hard constraint
If you might apply for medicine, dentistry or veterinary science, HL Chemistry is close to universally required and HL Biology is commonly expected alongside it. Engineering usually wants HL Maths and often HL Physics. Economics degrees at competitive universities increasingly require HL Maths, including courses that historically did not.
These are checkable facts rather than opinions. Look up the actual entry requirements for three or four courses you might apply to, at the universities you might apply to, and let that decide the subjects it decides. Nothing else in this article outranks it.
There is no such thing as an easy HL
Every year students pick a subject because it has a reputation for being manageable, and every year some of them find it is the one they struggle with. Difficulty in the IB is much more about fit than about the subject: whether you can write essays under time, whether you can hold a long calculation together, whether you can memorise a lot of precise vocabulary.
The better question is not which HL is easiest but which one you can still work at in March of your second year, when you are tired and the IA deadlines have all arrived at once.
Three HLs is the real workload question
The diploma is six subjects, three at higher level, plus TOK, CAS and the Extended Essay. The HL choice determines how much of your second year is spent on content you find heavy. Three HLs that all involve long written coursework is a very different year from three that do not.
Look at the internal assessments as well as the exams. The IA is a substantial piece of work in every subject and they tend to fall due at similar times.
Predicted grades matter more than prestige
Universities make offers on predicted grades. A student predicted 7 in a subject regarded as straightforward is in a stronger position than one predicted 5 in a subject regarded as demanding, for almost every course that does not specifically require the harder subject.
This is not an argument for avoiding difficulty. It is an argument against choosing a subject you will find punishing purely because it sounds impressive.
In short
- Check the entry requirements for real courses at real universities first.
- There is no easy HL. There is only fit.
- Look at the IAs, not just the exams - they land at the same time.
- Predicted grades open doors. Prestige on its own does not.
Put it into practice
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