Leeks might not be the first food you think of for iron, but this mild onion relative quietly packs about 2.1 mg of iron per 100 g raw — more than many leafy greens by weight. This calculator converts any portion of raw or cooked leeks into its iron content, Daily Value percentage, and optional absorption estimate, so you can see exactly what a cup of chopped leeks, a single medium stalk, or a whole serving adds to your daily need.
Whether you track micronutrients, manage anemia risk, follow a plant-forward diet, or simply want to understand your meals better, this tool is for you. Choose whether your leeks are raw or boiled, enter grams, ounces, cups or leek stalks, pick a reference value (FDA Daily Value or a common RDA), and get a clear breakdown plus the step-by-step math behind it.
Leek iron is non-heme iron, meaning your body absorbs it less readily than meat iron. That's why the optional absorption estimate is useful. Pair your leeks with vitamin C-rich foods and use the practical tips below to get the most from every portion.
🥬 Leek Iron Calculator
Enter a portion to see total iron, % Daily Value, and optional estimated absorbed iron.
1. Leek state
2. Portion size
3. Reference value for % target
⚙️ Optional absorption scenario
Enter a portion and press Calculate Iron to see results.
Reference Iron Values for Leeks
Values below are based on USDA FoodData Central for raw and boiled leeks. Cooked leeks show a lower value per 100 g partly because boiling adds water and can leach minerals into the cooking water. The table is a handy quick reference before you use the calculator for a custom portion.
| Portion | Weight | Iron | % DV (18 mg) |
|---|---|---|---|
| Raw leeks, 100 g | 100 g | 2.1 mg | 11.7% |
| Raw leeks, 1 cup chopped | ~89 g | 1.87 mg | 10.4% |
| 1 medium raw leek | ~89 g | 1.87 mg | 10.4% |
| Cooked leeks, 100 g | 100 g | 1.1 mg | 6.1% |
| Cooked leeks, 1 cup | ~104 g | 1.14 mg | 6.3% |
Serving sizes are approximate; weigh trimmed leeks whenever you need precise food-diary numbers.
How the Calculator Works
The math is a simple density conversion: iron (mg) = portion weight (g) ÷ 100 × iron per 100 g.
Raw leeks use 2.1 mg/100 g; boiled, drained leeks use 1.1 mg/100 g. The calculator converts ounces to grams with 1 oz = 28.3495 g, chopped cups to grams using about 89 g per raw cup and 104 g per cooked cup, and treats one medium leek as roughly 89 g. The % reference uses the FDA Daily Value of 18 mg unless you choose a more specific RDA target. Absorption scenarios multiply total iron by an estimated absorption rate; non-heme iron absorption can vary from about 3% to 18% depending on your iron status and meal contents. These are educational estimates, not medical advice. For a deeper background, see the NIH Iron Fact Sheet for Health Professionals.
Worked Examples
1 cup raw leeks. A raw chopped cup is about 89 g: iron = 89 ÷ 100 × 2.1 = 1.87 mg, or 10.4% of the 18 mg Daily Value.
200 g cooked leeks. Cooked leeks provide 1.1 mg/100 g, so 200 g gives 2.2 mg — 12.2% of the 18 mg reference, or 27.5% of an adult male's 8 mg RDA.
One medium raw leek. At roughly 89 g, one medium leek gives about 1.87 mg; two leeks in a soup provide about 3.7 mg, nearly 21% of the FDA Daily Value.
Tips to Get More Iron From Your Leeks
Pair with vitamin C. Lemon, tomatoes, red peppers, or greens help your body absorb non-heme iron more efficiently.
Limit tea and coffee at mealtimes. Tannins bind to non-heme iron and reduce absorption; try waiting an hour after eating.
Use cast-iron cookware. Acidic leek dishes cooked in a cast-iron pan can pick up meaningful additional iron.
Combine leeks with other plant iron sources. Beans, lentils, and fortified grains add up across the day. For more leek nutrient data, see the leek fiber calculator and the leek sodium calculator.
Common Mistakes to Avoid
Using raw values for cooked portions. Boiled leeks absorb water and can lose minerals to the cooking liquid, so raw density will overestimate cooked iron by roughly 2×.
Treating total iron as absorbed iron. Most non-heme iron passes through unabsorbed; the absorption estimate is more useful for diet planning.
Trusting average leek sizes. A medium leek can range from 60 to 150 g. Weigh your trimmed leeks for accurate tracking, and check whether packaged weights are trimmed or whole.
Frequently Asked Questions
Are leeks a good source of iron? They are a decent plant source — 2.1 mg per 100 g raw — but the iron is non-heme, so absorption is lower than from meat.
Why is cooked leek lower in iron per 100 g? Boiling adds water and can leach minerals into the cooking liquid, which dilutes the nutrient concentration by weight. The calculator applies the appropriate USDA-derived value for each state.
Can leeks alone meet my iron needs? No practical amount: reaching 18 mg would require roughly 857 g, or about 9 cups, of raw leeks. Treat leeks as one useful contributor in a varied, iron-conscious diet. If you are concerned about deficiency, talk to a doctor or registered dietitian before supplementing. More general guidance is available in the NIH Iron Consumer Fact Sheet.