Milligrams vs micrograms on supplement labels

This check covers US labels. Start with the exact package and variant you have, then use the steps below. Explore more supplements checks.

What to look at

1. Confirm that both figures describe the same nutrient.
2. Keep the serving size attached to each amount.
3. Convert mg to mcg by multiplying by 1,000 before comparing.

A little practice

Read this label.

A: 0.5 mg per serving. B: 500 mcg per serving of the same nutrient.

Illustrative excerpt · not a real product

Why this reading matters

A supplement label gives ingredients and amounts, but it does not establish whether you need the product. Independent quality seals do not guarantee that a supplement is effective or safe for everyone. NIH Office of Dietary Supplements.

What the label cannot settle

Do not use this mass conversion for IU or DFE, which require substance-specific interpretation. Equal quantities do not establish an appropriate dose for you.

Put the check to work

Compare the exact words and amounts on your package with the example. If a panel is missing, a photo is unreadable or the manufacturer has not disclosed a detail, keep that detail as unknown. A different flavor, shade or formulation needs its own check.

For the full reading method, use our supplements label guide. The medicines and supplements guide adds context for your needs.

A useful next check

• Comparing supplement prices per labeled serving
• The same nutrient in two supplements
• Which supplement details to bring before surgery

Sources read and this label example reviewed on 2026-09-24. Examples are illustrative, not product tests or clinical reviews.