Iron Labels: Elemental Amount, Serving Size, and Form

A practical way to compare iron products by the elemental iron printed on the label, serving size, form, and package count.

Iron products may list ferrous sulfate, ferrous gluconate, ferric citrate, or another compound. The compound weight is not the same as the elemental iron amount used for a label comparison.

Use the declared elemental iron

NIH ODS explains that elemental iron is listed in Supplement Facts, so shoppers do not need to calculate the iron fraction from a chemical form. Record that milligram amount, then copy the named compound and number of units per labeled serving. Do not compare two products by the weight of the capsule or iron salt.

Check serving and package details

Multiply elemental iron per serving by servings per container to calculate a package total for price comparison. Note whether a product is standalone iron or part of a multivitamin. Iron labels include a warning to keep the product out of children’s reach; read and follow the current package warnings. This page does not advise whether a person should use iron.

Frequently asked questions

Do I need to convert ferrous sulfate into elemental iron?

No. Use the elemental iron amount declared in Supplement Facts.

Can I use the same package-price calculation for a multivitamin?

Only if the label gives a clear iron amount and serving count. Keep the rest of the formula visible too.

Sources and review

Sources: NIH Office of Dietary Supplements, iron fact sheet and consumer information; FDA, Supplement Facts labeling guide. Reviewed September 28, 2026.

Use current SuppScan data

SuppScan presents the product data available in its catalog and does not manufacture missing values. Open the Other vitamins & minerals comparison to review current offers and normalized metrics.