Supplement Timing Calculator
Build a personalised supplement schedule. Enter which supplements you take and your wake, sleep, and workout times — get evidence-based timing recommendations for each.
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Why Timing Matters (For Some Supplements)
Supplement timing is one of the most confusing topics in nutrition — partly because it matters significantly for some supplements and almost not at all for others. Understanding which category each supplement falls into lets you prioritise what actually makes a difference.
High-Timing-Sensitivity Supplements
- Pre-workout: 30–60 minutes before exercise for peak caffeine levels during the session
- Berberine: Before carbohydrate-heavy meals — acts on glucose uptake pathways
- Casein protein: Before sleep — slow digestion provides overnight amino acid availability
- Magnesium: Evening — nervous system calming effect best used before sleep
Low-Timing-Sensitivity Supplements
- Creatine: Take consistently daily. Post-workout is slightly optimal on training days but the difference is small.
- Vitamin D: Any time with a fat-containing meal. Morning preferred for potential sleep quality reasons.
- Omega-3: With any fat-containing meal for absorption. Timing between meals has negligible difference.
- Collagen: Pre-exercise with vitamin C shows the best evidence for tendon/joint health.
Frequently Asked Questions
Does supplement timing really matter?
It depends on the supplement. For some, timing is critical: pre-workout needs 30–60 minutes before exercise; berberine works best taken before carbohydrate-heavy meals; magnesium is most effective at night. For others, consistency matters far more than timing: creatine produces the same results whether taken morning, post-workout, or evening — daily consistency is what matters. The calculator identifies which supplements are timing-sensitive and optimises your schedule accordingly.
What is the best time to take creatine?
On training days, post-workout with protein and carbohydrates may slightly improve creatine uptake into muscles. On rest days, any time of day is fine — take with a meal. The most important thing about creatine timing is that you take it every single day, including rest days. Missing days disrupts muscle creatine saturation.
When should I take vitamin D?
Vitamin D is fat-soluble and should be taken with a fat-containing meal for optimal absorption. Morning (with breakfast) is generally preferred, as some research suggests evening vitamin D can affect sleep quality by influencing melatonin pathways. Take with the meal that contains the most fat in your morning routine.
Can I take all my supplements at once?
Some supplements should not be combined: iron and calcium compete for absorption (separate by 2+ hours); zinc and iron compete; magnesium can interfere with iron absorption. Fat-soluble vitamins (A, D, E, K) should all be taken with food. Water-soluble vitamins (B complex, C) can be taken any time. The safest approach is to take performance supplements around training, health supplements with breakfast/dinner, and sleep supplements at bedtime.