Free tool
CBD dosage calculator
A conservative starting-dose estimate based on your body weight, experience, and what you're using CBD for. Start low, hold for a few days, increase only if needed.
Want the full reasoning? Read the complete dosage guide →
Inputs
Full-spectrum includes a legal trace of THC; broad-spectrum has the THC removed.
Your suggested starting dose
35 mg/day
≈ 1 mL per day (about 1 dropper) of your 1000 mg / 30 ml oil. Split AM/PM.
~0.5 mL AM and ~0.5 mL PM.
How to titrate from here
- Hold this starting dose for 5–7 days. Watch how you feel.
- If you need more, increase by 5 mg/day and hold another 5–7 days.
- Don't exceed 55 mg/day without speaking to a healthcare provider.
- If you take prescription medications, check interactions first.
Choosing full-spectrum vs THC-free
You’ve picked full-spectrum — it keeps the minor cannabinoids and a legal trace of THC.
If you’re drug-tested, sensitive to THC, pregnant or breastfeeding, or taking other medications, consider broad-spectrum (THC-free) instead — same CBD, no THC.
Either way, your starting dose above is the same — it’s based on CBD content, not spectrum. Start low and go slow.
Want to go deeper?
Complete dosage guide →
The full method behind this calculator — body weight, severity, condition, product type.
Bioavailability — why dosage varies →
Oil vs. gummy vs. cream: how much CBD your body actually absorbs.
CBD + your prescription meds →
CYP450 enzymes, the grapefruit rule, what to check before you start.
Side effects to watch for →
Dry mouth, drowsiness, GI changes — what's normal, what to flag.
CBD for sleep →
Timing, dosage windows, and what works for non-REM vs. sleep-onset issues.
CBD for pain →
Acute vs. chronic, topical vs. systemic, when to combine.
CBD for anxiety →
Why lower doses often work better, and what the research suggests.
Dosing for dogs →
Pets are different — body weight maths are similar, but spectrum and excipients matter more.
How this calculator works
The estimate starts from your body weight: published human studies have used a very wide range of CBD amounts, and most everyday users land far below the doses used in clinical research. We use a conservative 0.5–1.5 mg of CBD per kilogram of body weight per day, scaled by how strongly your symptoms affect you.
Two adjustments are applied on top. If you're new to CBD, the estimate is halved — individual sensitivity varies a lot, and the point of a starting dose is to find your minimum effective amount, not someone else's average. Your primary goal nudges the number too: lower for stress (where smaller amounts are commonly used), slightly higher for pain-related goals. The result is rounded to the nearest 5 mg and capped at 100 mg/day — above that, you should be talking to a healthcare provider, not a web calculator.
The output is a starting point, not a prescription. The full reasoning — including how product format changes absorption — is in the complete dosage guide.
Why the product format matters
The same milligrams behave differently depending on how you take them. Oil held under the tongue is absorbed partly through the mouth and tends to be felt sooner — typically within 15–45 minutes. Gummies and capsules pass through digestion first, so onset is slower (often 1–2 hours) but commonly lasts longer. That's why the calculator translates your daily milligrams into product-specific amounts — drops or millilitres of your oil, or a count of gummies or capsules at your product's strength — and why evening-only timing is suggested when sleep is the goal. Our bioavailability guide covers the absorption differences in detail.
Safety first
CBD is generally well tolerated in research settings, but it is not risk-free and it is not for everyone. Talk to your healthcare provider before starting if you take prescription medication (see the drug-interactions guide), are pregnant or breastfeeding, or have a liver condition. Common mild effects people report include drowsiness, dry mouth, and digestive changes — our side-effects overview covers what's typical and what should prompt you to stop and check with a professional. This calculator provides general information, not medical advice.
Frequently asked questions
- Why does the calculator give a lower dose for beginners?
- Individual response to CBD varies widely, and there is no universally agreed dose for any goal. Starting at roughly half the typical estimate lets you find the lowest amount that works for you while keeping side effects like drowsiness or dry mouth less likely. You can always titrate up in small steps — going slowly costs a week; starting too high wastes product and muddies what is actually helping.
- How long should I stay on a dose before increasing it?
- Hold each dose for five to seven days before changing it. CBD effects can build gradually, and day-to-day variation (sleep, stress, food) makes shorter trials unreliable. If nothing has changed after a full week, increase by about 5 mg per day and hold again.
- Does full-spectrum vs THC-free change the dose?
- No — this calculator doses by CBD content, which is the same in both. The spectrum choice is about product fit: full-spectrum keeps the minor cannabinoids and a legal trace of THC, while broad-spectrum has the THC removed, which matters if you are drug-tested, sensitive to THC, pregnant or breastfeeding, or taking other medications.
- Can I take CBD alongside prescription medication?
- Check with your healthcare provider or pharmacist first. CBD is processed by the same liver enzymes (the CYP450 family) as many common prescriptions, so it can change how those medications are metabolized — the same reason some medications carry a grapefruit warning. Our drug-interactions guide covers what to ask about.