The Kiwi Iron Calculator estimates the iron content of fresh kiwifruit from the amount you eat. Enter whole fruits, grams, or cups of sliced kiwi, and the tool converts your serving to milligrams of iron and compares it with a daily target tailored to your life stage. It is useful for anyone tracking iron intake, planning plant-forward meals, or checking whether a fruit snack makes a meaningful contribution to daily micronutrient needs.
The defaults are based on representative green kiwifruit values from USDA FoodData Central — about 0.31 mg iron per 100 g and 69 g for a medium fruit. You can adjust both values to match a specific label or cultivar. The calculator also shows how many kiwis would be needed to reach the selected RDA, which puts the fruit’s iron contribution into perspective.
Because kiwi is also rich in vitamin C and antioxidants, it can support iron absorption when paired with legumes or leafy greens. Use this tool as a planning aid, not as a substitute for professional dietary advice.
🥝 Kiwi Iron Calculator
📊 Results
How to Use This Tool
Pick a serving size that matches what you actually eat — whole medium kiwis, grams, or standard cups of sliced fruit. The preset buttons fill in common amounts for you. Then set the RDA row to your life stage or choose Custom RDA to enter a personal target from a dietitian or food tracker. Click Calculate to see total fruit weight, iron in milligrams, the percentage of your daily target, and how many kiwis it would take to hit 100% of that target.
If your kiwi’s nutrition label lists iron per serving, adjust the “mg iron per 100 g” field while keeping the serving size in mind — the tool uses 100 g as the base.
Formula Explained
The calculation is a simple proportion. First the tool converts your entry to grams: 1 medium kiwi = 69 g (edible portion), 1 cup sliced = 180 g. Then it applies the iron density:
Iron (mg) = grams of kiwi × iron per 100 g ÷ 100
Daily value is just that iron amount divided by your selected RDA, multiplied by 100. The “kiwis to reach 100% DV” figure works the same math backward: RDA ÷ iron per gram ÷ grams per kiwi, rounded up to the next whole fruit.
Worked Examples
Example 1: Adult female (19–50), RDA 18 mg, eats 2 medium kiwis. Weight = 2 × 69 = 138 g. Iron = 138 × 0.31 ÷ 100 = 0.428 mg. Daily value = 0.428 ÷ 18 × 100 = 2.4%.
Example 2: Adult male, RDA 8 mg, eats 1 cup sliced kiwi. Weight = 180 g. Iron = 180 × 0.31 ÷ 100 = 0.558 mg. Daily value = 0.558 ÷ 8 × 100 = 7.0%. To reach 8 mg he would need about 38 medium kiwis — illustrating that kiwi alone is not a high-iron food.
Reference Data
| Life stage | RDA for iron (mg/day) |
|---|---|
| Adult male (19–50) | 8 |
| Adult female (19–50) | 18 |
| Adult female (51+) | 8 |
| Pregnancy | 27 |
| Lactation | 10 |
These values are the U.S. Recommended Dietary Allowances from the National Institutes of Health. Iron needs can be higher for endurance athletes, heavy menstrual loss, or diagnosed deficiency — confirm your personal target with a healthcare professional.
Tips & Best Practices
- Pair kiwi with iron-rich plant foods: the vitamin C in kiwi helps convert non-heme iron into a more absorbable form.
- Use the “kiwis to reach 100% DV” line to teach portion reality — fruit contributes to micronutrient variety, not heavy iron loading.
- If you eat golden kiwi, check the label; cultivars can differ slightly in iron content.
- Adjust the reference data only when you have a reliable source, like a package label or a national food database.
Frequently Asked Questions
Is kiwi a good source of iron?
No single fruit is a major iron source. A medium kiwi provides roughly 0.21 mg of iron — about 1–3% of an adult’s daily target. Kiwi’s real benefit is vitamin C, which boosts absorption of iron from other foods eaten in the same meal.
Why does the tool use 180 g for a cup of sliced kiwi?
That is a common US-based estimate for sliced fruit density. Whole kiwi packed differently, so weights may vary by a few grams; the reference fields let you fine-tune the value.
Can I use this for dried kiwi?
No — dried fruit has a very different water and nutrient density. This tool is calibrated for fresh, raw kiwi only.
Where do the reference values come from?
The USDA FoodData Central entry for raw kiwifruit (green) lists 0.31 mg iron per 100 g and about 69 g per medium fruit. You can browse that database at fdc.nal.usda.gov.