Caffeine calculator: milligram comparisons and Taiwan tiers
Milligram comparison (derived, never measured)
Enter the drink's caffeine milligrams (a label / self-reported value, never measured by this tool) against the FDA line (authorized paraphrase): 400 mg a day for most adults. Every comparison is derived, never measured: the line is an authorized anchor, your input is a label value, and their comparison is a derivation, not a measured equivalence.
FDA consumer page, checked 2026-09-30: for most adults, 400 mg a day is an amount not generally associated with negative effects. The FDA presents this as a reference, not a safety limit.
For those trying to become pregnant, pregnant, or breastfeeding, the FDA recommends asking a health care provider whether caffeine should be limited. The page gives no numeric threshold (checked 2026-09-30).
Taiwan tier demo
Enter mg per 100 mL + drink type to see the tier: ≥20 exact / <20 ceiling (shows ≤ ceiling) / coffee-tea-cocoa ≤2 low caffeine. Instant sachets label the per-serving total. Rule text on the method page, S-TFDA-quote.
≥20: exact label
Caffeine ≥20 mg/100mL: labeled in mg per 100 mL (exact value).
<20: ceiling label
Caffeine <20 mg/100mL: may be labeled “20mg/100mL以下” — a ceiling, not an exact value; the calculator shows ≤ ceiling.
≤2 (coffee/tea/cocoa): low caffeine
Coffee/tea/cocoa drinks at ≤2 mg/100mL may be labeled “低咖啡因”.
Instant sachets: total per serving
Powder products for reconstitution: labeled with total caffeine per serving (mg).