🧂 Japan Salt Intake Calculator (Na mg to Salt g)

Japanese food labels show sodium (ナトリウム) in milligrams, not salt. To convert, multiply by 2.54 and divide by 1,000: salt (g) = Na (mg) × 2.54 / 1000. This works because table salt is about 39% sodium by weight (23 / 58.44).

The Japanese Ministry of Health, Labour and Welfare (MHLW) sets a daily salt target of under 7.5 g for men and under 6.5 g for women (Dietary Reference Intakes for Japanese, 2020 edition). The World Health Organization recommends under 5 g for everyone, and the American Heart Association goes further at under 2.3 g. Japanese diets are traditionally high in salt from soy sauce, miso, pickles and processed foods, so converting label values into grams makes it easy to track your day.

The tool converts in both directions. Type the sodium value from a food label (mg) and you get the salt equivalent in grams; type salt grams and you get sodium in milligrams. It also shows what fraction of the MHLW daily target that amount represents for men and women.

For a full day, add up the salt from each item you ate. As a rough reference: one bowl of miso soup ~1.5 g, one bowl of udon ~4-6 g, one portion of curry rice ~3-4 g, two slices of bread ~1 g, and a tablespoon of soy sauce ~2.6 g. The tool is a convenient converter - it does not track meals or diagnose health conditions.

1. Find the sodium (ナトリウム) value on the nutrition label, in mg.
2. Enter it in the sodium field - the salt equivalent appears instantly.
3. Or enter a salt amount in grams to reverse the conversion.
4. Check the percentage of the MHLW daily target for your gender.
5. Add up the salt from each meal to estimate your daily total.

Why do we multiply sodium by 2.54 to get salt?

Table salt (NaCl) is 23 / 58.44 = 39.3% sodium by weight. To find the salt mass that contains a given sodium mass you divide by 0.393, which equals multiplying by 2.54.

What is the daily salt limit for adults in Japan?

The MHLW target (2020 edition) is under 7.5 g per day for men and under 6.5 g for women. The WHO recommends under 5 g for everyone.

How much salt is in a bowl of miso soup?

Around 1.2-1.5 g per bowl, depending on the miso and dashi. Instant miso soup packets are usually 1.5-2.5 g.

Is 6,000 mg of sodium a lot?

Yes - 6,000 mg is 15.2 g of salt, roughly twice the Japanese male daily target and three times the WHO limit.

Do Japanese food labels show salt or sodium?

Most show both: sodium (ナトリウム) in mg and often the equivalent salt (食塩相当量) in grams. When only sodium is shown, multiply by 2.54 to convert.

Is this tool medical advice?

No. It is an educational converter. Dietary targets are population guidelines; if you manage high blood pressure or kidney disease, follow the limit given by your doctor.

Read the sodium line, not the salt line - some imported products label only sodium. A quick mental shortcut: 1,000 mg Na ≈ 2.5 g salt. When eating out, assume restaurant ramen, soba and curry are 4-6 g of salt per bowl, which alone nearly reaches the female target. Season with umami from dashi, citrus and spices instead of adding salt. If you have high blood pressure or kidney disease, consult your doctor; the MHLW targets are population guidelines and your individual limit may be lower. Check the Washoku recipe scaler to halve soy sauce and miso quantities in recipes without losing flavour.