If you have four weeks until the General Pharmaceutical Council (GPhC) Registration Assessment and your calculation skills need serious work, this plan gives you a structured path from shaky to exam-ready. It focuses entirely on Part 1 preparation — 40 calculations in 2 hours.
Four weeks is tight but realistic, provided you commit to daily practice and honest error review.
Before you start: baseline assessment
Before diving in, do a timed set of 20 mixed calculations covering all the main categories. Score it honestly. This tells you where you are starting from and which topics need the most attention.
Categories to cover in your baseline:
- Doses and dosing
- Concentrations (percentage and ratio strength)
- Dilutions
- Infusion rates
- Moles and millimoles
- Displacement values
- Unit conversions
- Quantity to supply
Note which categories you got wrong and why. This baseline steers your entire four weeks.
Week 1: Foundations and weak areas
Goal: Rebuild or solidify your method for each calculation type. Speed does not matter yet — accuracy and understanding do.
Daily routine (45 to 60 minutes):
- Morning (20 minutes): 5 to 8 calculations from one specific category, untimed. Work through each step fully. Check answers and review every error in detail.
- Evening (20 to 30 minutes): 5 to 8 calculations from a different category, same approach.
Topic schedule:
- Day 1–2: Doses and dosing (weight-based, paediatric, divided doses, renal adjustment)
- Day 3: Concentrations — percentage w/v, w/w, v/v. Make sure you know the definitions, not just the formulas.
- Day 4: Ratio strengths and conversions between ratio strength, percentage and mg/mL
- Day 5: Dilutions — C1V1 = C2V2 method
- Day 6: Infusion rates — volume/time, dose-based rates, drop rates
- Day 7: Rest or light review of errors from the week
End of week 1 check: Redo 5 questions from your weakest category. If you are still making conceptual errors (wrong method, not just arithmetic slips), spend more time on worked examples before moving on.
Week 2: Build speed and add complexity
Goal: Transition from untimed to timed practice. Start doing mixed sets rather than single-category practice.
Daily routine (45 to 60 minutes):
- Timed set (25 to 30 minutes): 10 mixed calculations. Aim for 3 minutes each. Do not pause to look things up — work straight through as if it is the real exam.
- Review (15 to 20 minutes): Go through every question. For wrong answers, identify whether the error was conceptual, a unit conversion mistake, arithmetic, or misreading the question. Log it.
Topic schedule:
- Day 1: Mixed set (all categories)
- Day 2: Focused set on moles and millimoles if this was weak in week 1, otherwise mixed
- Day 3: Mixed set plus 5 displacement value questions (candidates often underestimate these)
- Day 4: Mixed set
- Day 5: Focused set on infusion rates (the most multi-step category, so benefits from dedicated practice)
- Day 6: Mixed set — try to include at least one question from every category
- Day 7: Rest or error log review
End of week 2 check: You should be completing 10 questions in under 30 minutes with at least 70% accuracy on mixed sets. If you are below that, do not panic — but increase your daily volume to 12 to 15 questions.
Week 3: Exam-pace practice and error elimination
Goal: Build up to full-length sets at exam pace. Focus ruthlessly on eliminating repeat errors.
Daily routine (60 to 75 minutes):
- Timed set (40 to 45 minutes): 15 mixed calculations at exam pace.
- Review (20 to 30 minutes): Full review with error logging. By now your error log should show clear patterns — the same two or three error types appearing repeatedly.
Additional this week:
- Mid-week mock (Day 4): Do a full 40-question timed set in 2 hours. Sit it properly — block out the time, no interruptions, no reference materials. Review it thoroughly afterwards.
- Error-focused sessions: On days when your timed set reveals a persistent weakness, add 5 to 10 extra questions targeting that specific category.
Topic priorities this week:
Whatever your error log says. If you are consistently losing marks on infusion rates and ratio strengths, those get extra time. If dosing calculations are strong, spend less time on them and redirect to weaker areas.
End of week 3 check: On your mid-week mock, aim for at least 75% accuracy. Check your timing — if you ran out of time, identify which questions took too long and practise that type for speed.
Week 4: Full mocks and final polish
Goal: Simulate exam conditions repeatedly. Build stamina and confidence. Fix any remaining weak spots.
Daily routine:
- Day 1: Full 40-question mock, timed at 2 hours. Complete review afterwards.
- Day 2: Recovery day — light practice. Review the mock errors. Do a 10-question focused set on the weakest category from the mock.
- Day 3: Full 40-question mock. Different question source if possible.
- Day 4: Review and error analysis from Day 3 mock. Focused drill on any remaining problem areas.
- Day 5: Final 40-question mock. Treat this as a dress rehearsal — full exam conditions.
- Day 6: Light review of error log only. No heavy practice. Read through your most common errors one last time.
- Day 7 (exam day or day before): Rest. You have done the work.
Target this week: 80%+ on full mocks. If you are consistently hitting that, your calculation skills are in good shape. If you are around 70 to 75%, you can still pass — but keep targeting your weak areas in the remaining days.
Key principles throughout
Write out every step. Do not skip calculations or do them in your head. Write out unit conversions, formula setup, and intermediate steps. This is how you catch errors.
Convert units before calculating. This is the single most common source of error. Always ensure everything is in the same units before you start the arithmetic.
Sense-check every answer. Does it make clinical sense? A dose of 50 g for a patient, an infusion rate of 1,000 mL/hour, a supply of 3 tablets for a 7-day course — these should all trigger a recheck.
Review every error. The review is more important than the practice set itself. An error you understand and fix is progress. An error you ignore will happen again.
Do not skip rest days. Mental fatigue degrades calculation accuracy. One rest day per week protects the quality of the other six.
Quick FAQs
- Is four weeks enough for calculations? Yes, if you practise daily and review honestly. Four weeks of focused, structured practice is better than three months of sporadic, unfocused study.
- What if I fail the baseline assessment badly? Then you know exactly where you need to work. Extend week 1 by a few days if needed, and consider simplifying — start with the easiest calculation types to build confidence before tackling multi-step problems.
- Should I also study Part 2 topics during this time? Yes. This plan takes 45 to 75 minutes per day, which leaves time for Part 2 revision. Ideally, split your daily study between calculations and Part 2 content. Do not neglect one paper entirely.
- What calculator do I get in the exam? An on-screen calculator is provided. Some candidates find this slower than a physical calculator, so practise using a basic on-screen calculator during your mocks to get comfortable with it.