When people ask, “How long should I revise for each IB subject?” they’re usually asking something more honest:
“How do I stop feeling behind, without burning out?”
Because IB revision doesn’t fail from laziness. It fails from vagueness. You sit down, open a book, scroll for a while, and stand up later with the strange exhaustion of someone who worked hard on the wrong thing.
The goal of this guide is to give you a time plan you can trust, and a way to adjust it when real life (IAs, deadlines, tiredness) inevitably shows up.
The simple weekly rule for IB revision time
Here’s the most reliable baseline for IB students preparing for exams:
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HL subjects: 6-8 hours per subject per week
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SL subjects: 4-6 hours per subject per week
This isn’t about “studying more.” It’s about matching time to what the IB actually demands: depth, accuracy, and exam technique.
If you want a broader weekly-hours view (especially as exams approach), pair this with How Many Hours Should IB Students Study?.
A quick checklist before you allocate hours
Before you decide exact numbers, run this five-point IB checklist:
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Which subjects are HL and which are SL?
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Which subjects lose marks from content gaps (not just speed)?
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Which subjects lose marks from technique (command terms, structure, evaluation)?
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Which subjects have the most papers or the longest writing time?
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Which subject currently drains you emotionally (often a sign it needs structure, not more hours)?
If your schedule is messy, use this companion guide: How to Create a Balanced IB Study Schedule.
How long should you revise for HL vs SL IB subjects?
HL time is heavier for a boring reason: HL questions punish shallow understanding. They require more steps, more explanation, and more precision under pressure.
So if your week is limited, a helpful default is to weight your IB time like this:
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60% of your revision time to HL
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40% of your revision time to SL
Then customize.
A realistic weekly example (3 HL + 3 SL)
A typical IB combo might look like:
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HL: 3 subjects × 7 hours = 21 hours/week
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SL: 3 subjects × 5 hours = 15 hours/week
That’s ~36 hours/week of subject revision.
Important: that’s just subjects. You still need space for TOK, EE, IAs, and normal life. The best IB schedules don’t deny reality; they budget for it.
The best way to spend your IB hours (so they count)
Two students can both do “six hours of IB Biology.” One improves fast. One doesn’t.
The difference is what the hours contain.
A strong split for most IB subjects:
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60-70% practice questions + marking
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20-30% concept rebuild (notes, examples, micro-topics)
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10% planning + error log
This is where RevisionDojo becomes less like a resource and more like a system.
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Use the Questionbank to make practice your default, not your “if there’s time.”
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Use IB Flashcards with Spaced Repetition (SRS) for daily memory maintenance.
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Use the Flashcards feature to turn weak notes into quick recall.
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Use AI Chat to ask, “What would earn full marks here?” while the mistake is still fresh.
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Use Grading tools when written responses are the bottleneck.
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Use Predicted Papers and Mock Exams when timing and stamina are the bottleneck.
A weekly IB structure you can copy (without overthinking)
Try this repeatable rhythm for each IB subject:
Two shorter weekday sessions (45-60 minutes)
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10 min: quick concept refresh (one micro-topic)
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25-35 min: focused Questionbank set
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10 min: mark + write 1-3 “error rules”
One longer weekend session (90-120 minutes)
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45-60 min: mixed practice or a timed section
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20-30 min: review errors and rebuild the weakest subtopic
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10-15 min: flashcards to lock in recall
This kind of structure is explained even more concretely in Is 4 Hours of Study Enough for IB?.
How to ramp up IB revision as exams get closer
One of the biggest IB mistakes is jumping from “barely revising” to “three hours a night” in a week. It feels heroic, then collapses.
Instead, increase gradually:
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3-4 months out: keep baseline hours, focus on coverage + fixing chronic weak topics
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6-8 weeks out: increase hours by 30-60%, add weekly timed work
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Final month: more timed practice, more review, fewer new notes
For realistic timelines (not fantasy routines), see How Long Did It Take to Study for the IB Exams? and Is 1 Month Enough to Study for IB Exams?.
Use subject type to adjust your IB hours
Not all IB subjects spend time the same way.
Content-heavy sciences (Biology, Chemistry, Physics)
You usually need more time early for rebuilding foundations, then heavy practice later.
A good move is to anchor your revision in a subject hub (example: IB Biology Resources) and run a loop: Notes: Questions; Feedback; Flashcards.
Math subjects
Math rewards volume and variety. More frequent, shorter sessions beat one long weekly block.
Questionbank drilling matters here because it teaches patterns, not just content.
Essay-heavy humanities and languages
Hours should tilt toward writing under constraints: plans, timed paragraphs, and criterion-focused improvement.
This is where Tutors, the Coursework Library, and Grading tools can save hours by making feedback immediate and specific.
The takeaway: give each IB subject a budget, then make it measurable
So, how long should you revise for each IB subject?
Start here:
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HL: 6-8 hours/week
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SL: 4-6 hours/week
Then protect quality: make most of those hours active, marked, and specific.
If you want the easiest way to run this without reinventing your routine every day, build your week inside RevisionDojo: practice with the Questionbank, retain with Flashcards, clarify with AI Chat, rehearse with Predicted Papers and Mock Exams, and tighten your writing using Grading tools, the Coursework Library, and Tutors.
Your IB schedule doesn’t need to be perfect. It needs to be repeatable. And repeatable is what gets you to calm confidence on exam day.