Which type has most iron?

Dark, by far (~12 mg/100 g). Milk has ~2.4 mg, white under 1 mg.

Typically 5–10 g. Enter grams for accuracy — squares vary by brand.

Dark has ~80 mg/100 g. Not covered here — see the Coffee calculators for caffeine math.

Chocolate Calculator

By Zencalcy Editorial TeamLast reviewed September 2026About us

Dark chocolate is a real mineral source: ~230 mg magnesium per 100 g. Enter any amount of dark, milk, or white chocolate for magnesium, iron, and fiber.

Chocolate Calculator

Magnesium, iron, and fiber in any bar or square.

Configuration

Amount (grams)
Type

Enter values and calculate

How to use this calculator

Enter the amount in grams.
Pick the chocolate type.
Click Calculate.

Formula

nutrient = amount × (nutrient per 100 g ÷ 100)

Reference values per 100 g — dark (70%): Mg 228 mg, Fe 12 mg, fiber 11 g · milk: Mg 63 mg, Fe 2.4 mg, fiber 3.4 g · white: Mg 26 mg, Fe 0.9 mg, fiber 0.2 g.