Free supplement, sleep, blood-test and brain tools, each answering one question with the source named. Search, pick a topic, or scroll through them all.
Sleep
Melatonin timing, magnesium, glycine, L-theanine, valerian, chamomile and tart cherry: your amount against what the sleep trials gave.
- Melatonin Dose & Timing CalculatorWhen to take melatonin for your bedtime, and where your label sits among the doses the sources used.
- Tart Cherry Juice for SleepYour tart cherry against what the six sleep trials gave and found — including the two that found nothing.
- L-Theanine for SleepYour L-theanine against what the sleep trials gave, when, and what they found — mixed results included.
- Magnesium for SleepYour magnesium against what the sleep trials gave, when, and what they found — and the 350 mg limit.
- Valerian for SleepYour valerian, extract or root, against what twenty sleep trials gave and found — mixed results included.
- Glycine for SleepYour glycine — or the glycine in your magnesium glycinate — against the 3 g the sleep trials gave, and what they found.
- Chamomile for SleepYour chamomile tea or capsule against what the sleep trials gave, whether they had a placebo, and what they found.
Blood test results
Where a lab result sits: vitamin D, ferritin, TIBC, hemoglobin, B12, magnesium, potassium, the red-cell counts and free testosterone.
- Vitamin D Blood Level RangesYour vitamin D blood test in both units, and where it sits in the NIH’s own table.
- Ferritin Level CheckerYour ferritin result against the NIH’s and the WHO’s lines, and what inflammation does to it.
- Free Testosterone CalculatorFree and bioavailable testosterone from your own lab results, and the harmonized range for your age.
- Magnesium Blood Level RangesYour magnesium blood test in all three units, against the NIH’s range and a lab’s.
- Hemoglobin Level CheckerYour hemoglobin result against the NIH’s and the WHO’s 2024 lines, with the WHO’s altitude and smoking corrections.
- Vitamin B12 Level CheckerYour vitamin B12 blood test against the NIH’s lines — and the grey zone a “normal” result can hide.
- Potassium Level CheckerYour potassium blood test against the NIH’s range and two lab ranges — and what moves the number.
- Hematocrit Level CheckerYour hematocrit against the NIH’s range and MedlinePlus’s current one — by sex, pregnancy and age.
- MCV Level CheckerYour red cells’ average size against the 80–100 fL range — and what a small or large MCV may point to.
- Red Blood Cell Count CheckerYour red blood cell count against both ranges MedlinePlus prints — and what it says raises or lowers it.
- Reticulocyte Count CheckerYour reticulocyte count against the adult ranges MedlinePlus and Mayo Clinic Laboratories print — and what moves it.
- TIBC Level CheckerYour TIBC against the adult ranges MedlinePlus and Mayo Clinic Laboratories print — and your iron saturation from it.
Vitamins & minerals
The RDA and upper limit, vitamin D in IU, which magnesium or iron form, what to take together, and when to take an iron tablet.
- Magnesium Form Finder & Dose ChartWhich magnesium for what, and how much of the capsule is really magnesium.
- Vitamin D Dose CalculatorIU, mcg or mg — your vitamin D converted and placed between the RDA and the upper limit.
- Vitamin & Mineral Dose LookupThe RDA and the upper limit for every vitamin and mineral, by age — and where your label sits.
- Nutrient Pairing CheckerWhich supplements to take together, which to space apart, and when — each rule with its source.
- Iron, Zinc & Calcium Form FinderHow much of an iron, zinc or calcium tablet is the mineral itself — every form side by side.
- Magnesium Gummies CalculatorMagnesium per gummy, against the upper limit for adults and children, and the sugar that comes with it.
- Potassium Supplement CalculatorWhy potassium pills hold 99 mg, what citrate, gluconate and chloride really give, and the daily intake beside it.
- Iron Tablet Timing PlannerThe clear windows in your day for an iron tablet — around meals, coffee, dairy and calcium, by the NHS’s rules.
Caffeine, coffee & tea
How long caffeine lasts, what is in your cup, and matcha, yerba mate and tea against coffee — with L-theanine.
- Caffeine Half-Life & Sleep Cutoff CalculatorHow much caffeine is left at bedtime, and the latest time for your last coffee.
- Caffeine Content Chart & Daily LimitThe caffeine in every common drink, and your day added up against the FDA’s 400 mg.
- Matcha vs CoffeeCaffeine in a cup of matcha (143 measured samples) against coffee, the L-theanine, and the cost per cup.
- Yerba Mate vs CoffeeCaffeine in yerba mate — a cup, a refilled gourd or a can — against coffee, from measured samples.
- Caffeine + L-theanine RatioYour L-theanine to caffeine ratio against what the twelve trials of the pair gave — and what each found.
- Tea Caffeine vs CoffeeThe caffeine in your tea by type, steep time and water — measured, against the same cup of coffee.
Brain tests & focus
Reaction time, memory and attention tests, dual n-back, nootropic label doses, lion’s mane, and caffeine with L-theanine.
- Reaction Time TestFive rounds, your median in milliseconds, and the published average for your age.
- Nootropic Ingredient Dose CheckerIs the label dosed like the studies? Type the milligrams and see.
- Memory, Attention & Stroop TestsNumber memory, square memory and the Stroop colour test — one score page, saved in your browser.
- Dual N-BackThe working-memory drill from the 2008 study, played in your browser — and what the trials since found.
Herbs & mushrooms
Ashwagandha, lion’s mane, valerian and chamomile: what the trials gave, by extract and form, and what they found.
Creatine & workouts
Creatine dose and timing for your weight, monohydrate against HCl, and how many creatine gummies make a dose.
- Creatine Dose & Timing CalculatorYour loading and daily creatine dose in grams, from the published position stand.
- Creatine Monohydrate vs HCl CalculatorWhat HCl really costs per gram of creatine, and what the studies found.
- Creatine Gummies CalculatorHow many gummies make 3–5 g of creatine, what it costs against powder, and the sugar a day.
Electrolytes & hydration
Electrolyte powder labels, coconut water against sports drinks and milk, and potassium supplements and blood levels.
Labels, cost & quality
Is it third-party tested, does the label reach the studied dose, how many gummies make a dose, and what it costs you a day.
Is it working?
How long a supplement takes to work, by what the trials measured, and a four-week tracker to see it for yourself.
Most supplement questions have a number for an answer, and the number is usually missing from the bottle: how many grams of creatine for your body weight, how much actual magnesium is in a 500 mg capsule, whether the 50 mg of an ingredient on a label is anywhere near the dose the studies used, how long the coffee you drank at four o’clock will still be in you at bedtime, where 2,000 IU of vitamin D sits against the upper limit, and whether your memory scores moved after four weeks on something. These free tools work that out from what you type, in a few seconds, on a phone as well as a laptop. Nothing to sign up for, nothing to install.
Where the numbers come from
Every dose, limit and conversion here is taken from an official source and named on the page — the National Institutes of Health Office of Dietary Supplements, the FDA, the published Dietary Reference Intakes, or a peer-reviewed position stand — with the date it was last checked. Where good sources disagree, you see both numbers and who said each one, because pretending there is a single answer would be the easiest way to be wrong.
What these tools will never do
They do not diagnose anything, they do not tell you a supplement treats a condition, and they do not check whether a supplement interacts with your medication — that last one is a job for your pharmacist and for a proper drug-interaction database, and doing it badly would hurt somebody. Nothing here recommends a dose above the official upper limit. This is not medical advice: talk to your doctor or pharmacist before starting anything new, especially if you take blood thinners, antidepressants or blood-pressure medication.
What you type stays on your device
Every calculation runs inside your own browser. A weight, a lab result or a label you type is never sent anywhere and never stored by us.
Share an answer, or keep it
Every result has its own link. Copy link saves exactly what you entered, so you can send a dose to someone or open it again on your phone in the shop without filling the form in twice.
Put a tool on your own site
Every tool has an Embed button. It gives you a short piece of code to paste into a page on your own blog or forum. The tool works there exactly as it does here, free, with a credit line linking back to Valentino’s Naturals.
More from Valentino’s Naturals
The tools answer the quick questions. For what actually happened when I took the stuff — one product at a time, four weeks minimum, including the times nothing did — start with the latest reviews.