Caffeine Calculator: How Much Caffeine in Your Day?
Add up the coffee, tea, energy drinks and soda in your day and see your total caffeine against the 400 mg daily safe limit — with what to do if you go over.
| Source | Typical serving | Caffeine |
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Typical values; actual caffeine varies a lot by brand, brew strength and cup size.
How much caffeine is too much?
For most healthy adults the FDA puts the safe ceiling at about 400 milligrams of caffeine a day — roughly four 8-ounce cups of brewed coffee. That is a population guideline, not a personal prescription: sensitivity varies with body weight, medication and how used to caffeine you are.
In pregnancy the advice is stricter. Most health bodies suggest keeping caffeine under 200 mg a day. If that applies to you, treat 200 mg, not 400, as your line.
Why the numbers are only a guide
Caffeine content swings widely by brand and preparation. A generic cup of coffee is anywhere from 70 to 140 mg depending on the beans, the grind and how long it brews; energy drinks range from 40 mg to over 300 mg per can. The figures here are typical values — for anything packaged, the label is the truth.
Caffeine, answered
How much caffeine is too much?
For most healthy adults, more than 400 mg a day — about four cups of coffee — raises the risk of side effects like insomnia, jitteriness and a racing heart. Sensitivity varies, so some feel it well below that.
How long does caffeine stay in your system?
Caffeine has a half-life of roughly 5–6 hours, so half is gone in that time and it can take 10–12 hours to clear most of it. That is why an afternoon coffee can still affect sleep.
What can I drink instead once I hit my limit?
Switch to water, herbal or rooibos tea, decaf coffee, or sparkling water — the ritual without the caffeine.
Is caffeine safe during pregnancy?
Most guidance advises staying under about 200 mg a day during pregnancy — roughly one to two cups of coffee. Check with your provider for personal advice.
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