Learning how to choose your IB subjects, and which to take at Higher Level versus Standard Level, is one of the first major decisions of the Diploma Programme — and getting it right early avoids a much harder correction later.
The Basic Requirement
You need six subjects, one from each of the first five groups plus a sixth from the Arts or an additional Group 1-4 subject, with three at Higher Level (HL) and three at Standard Level (SL) as the standard split. See our full guide on how many HL subjects you should take for when a fourth HL is genuinely worth considering.
How HL and SL Actually Differ
HL subjects cover more content over 240 teaching hours; SL subjects cover less over 150 hours. This isn’t just “more work” — HL often goes into greater depth and complexity, not just more breadth of the same material, and this distinction matters for both your workload and how universities read your profile later.
Choosing Based on Genuine Strength, Not Just Interest
A subject you enjoy but don’t naturally excel in can still be a reasonable SL choice; a subject central to your intended degree is usually worth prioritizing at HL if you can realistically score well in it. If you already have a career direction in mind, see our guides on the best subject combinations for Medicine or Engineering for how specific fields shape this decision.
Choosing Based on University Requirements
If you already have a general direction in mind, check whether your target courses require specific subjects at HL (common for Medicine, Engineering, and quantitative degrees) before finalizing your combination — committing to the wrong level in a required subject can close doors later, sometimes without you realizing it until applications.
A Practical Framework for Deciding Each Subject
For each of your six subjects, ask three questions in order: Do I need this specific subject (and level) for a course I’m seriously considering? Am I genuinely strong in it, based on real evidence like recent grades, not just enjoyment? Can I realistically sustain three HL subjects at this combined difficulty without an unmanageable workload? A subject that fails the second question is a reasonable SL candidate even if you’re drawn to it; a subject required by a specific course usually overrides a mild preference elsewhere.
Common Mistakes When Choosing
- Choosing HL subjects based purely on what “sounds impressive” rather than genuine strength
- Ignoring specific HL subject requirements for your intended degree until it’s too late to change
- Not considering realistic workload balance across your three HL subjects together, not just individually
- Assuming you can freely switch later — see our guide on whether you can still change IB subjects for how narrow that window actually is
If You’re Still Genuinely Undecided
If two subjects feel equally strong and equally relevant, our guide on the easiest IB subjects to score a 7 in can help break the tie using realistic grade-boundary patterns rather than guesswork — though fit and genuine interest should still outweigh this if the difference is small.
Final Tip
If you’re torn between two subjects for your sixth choice, ask your school’s IB coordinator which pairing has historically produced the most balanced workload for students with a similar profile to yours — this kind of practical, school-specific insight is more useful than generic online advice.