Calories in Seaweed: Spirulina, Wakame, Kelp, Laver

By NYUS Inc. · Published 29 October 2026

"Spirulina calories", "seaweed calories" and "nori calories" are searched in India, and no NYUS page answers them. This guide gives the eight seaweed records the USDA FoodData Central SR Legacy table has outside agar, per 100 g and in the household portions USDA prints: dried and raw spirulina, raw laver, wakame, kelp and Irish moss, and dried and rehydrated Canadian cultivated Emi-tsunomata. IFCT 2017, the Indian Food Composition Tables from ICMR-NIN, has no seaweed or spirulina row, so this page uses SR Legacy only. Agar, the setting seaweed, is in our jelly, gelatin and agar guide; low-sodium vegetarian foods are in our low sodium vegetarian foods page and fibre-rich vegetarian foods in our high fibre vegetarian foods page.

The short answer

By USDA SR Legacy, raw seaweed is 26 kcal per 100 g for raw spirulina (170091), 35 kcal for laver (168458), 43 kcal for kelp (168457), 45 kcal for wakame (170496) and 49 kcal for Irish moss (168456). Dried spirulina (170495) is 290 kcal per 100 g, and dried Canadian cultivated Emi-tsunomata (167602) is 259 kcal. Our reading: dried and raw rows are different weights of the same kind of food, so the 290 against 26 kcal for spirulina is mostly water (4.68 g against 90.7 g per 100 g), not a different food; among the raw rows raw spirulina has the most protein (5.92 g) with laver second (5.81 g); and wakame has the most sodium of the raw rows (872 mg) with laver the least (48 mg).

USDA SR Legacy: per 100 g

Figures are as the USDA record pages print them, read on 29 October 2026. Energy is USDA's own kcal with the kJ it prints beside it; water, protein, total fat and carbohydrate (by difference) are in g, fibre in g and sodium in mg, all per 100 g. USDA labels the kcal on every row as Calculated; on the two Emi-tsunomata rows water, protein, fat, fibre and sodium are Analytical, and kcal, kJ and carbohydrate by difference are Calculated. These are US records on US samples, not Indian averages, and IFCT 2017 has no row for any of them.

The household portions USDA prints

USDA prints these portions on the records below; the other records have none. The kcal in the last column is ours: the printed kcal per 100 g times the grams, divided by 100, shown to 0.1 with half rounding up. The 10 sheets (26 g) portion is printed on the raw laver record, so it describes raw laver, not a packet of toasted or seasoned nori sheets; we do not say how a packet's sheets weigh, and USDA prints no per-teaspoon weight for spirulina or anything else.

The portion sums: 170495 1 cup (112 g): 290 × 112 / 100 = 324.80, so 324.8 kcal; 170495 1 tablespoon (7 g): 290 × 7 / 100 = 20.30, so 20.3 kcal; 168458 10 sheets (26 g): 35 × 26 / 100 = 9.10, so 9.1 kcal; 168458 2 tbsp (1/8 cup) (10 g): 35 × 10 / 100 = 3.50, so 3.5 kcal; 170496 2 tbsp (1/8 cup) (10 g): 45 × 10 / 100 = 4.50, so 4.5 kcal; 168457 2 tbsp (1/8 cup) (10 g): 43 × 10 / 100 = 4.30, so 4.3 kcal; 168456 2 tbsp (1/8 cup) (10 g): 49 × 10 / 100 = 4.90, so 4.9 kcal; 167602 0.25 cup (5 g): 259 × 5 / 100 = 12.95, so 13.0 kcal; 167603 0.25 cup (25 g): 31 × 25 / 100 = 7.75, so 7.8 kcal.

What stands out in the numbers

• Dried spirulina is the densest row: 290 kcal and 57.5 g protein per 100 g, against 26 kcal and 5.92 g for raw spirulina; the difference is water (4.68 g against 90.7 g per 100 g). A tablespoon of dried spirulina is a small weight, 20.3 kcal for 7 g by our arithmetic, so the printed tablespoon is the figure to use for it, not per 100 g.
• Raw rows are all light per 100 g: 26 to 49 kcal, and a printed 2 tbsp (10 g) portion of raw kelp is 4.3 kcal and of Irish moss 4.9 kcal by our arithmetic.
• Sodium differs a lot: 48 mg (laver) to 872 mg (wakame) per 100 g among the raw rows, and 4330 mg per 100 g for dried Emi-tsunomata, the highest row, which also has the most fibre (36.7 g). We show them as printed.

Why these are reference rows, not your packet

• No nori row. The SR Legacy record is named laver; a search for nori finds nothing. We do not say a seasoned, roasted or sushi nori sheet equals it.
• Raw, dried and rehydrated are different weights. Log the one you actually weighed; the per-100 g rows are not interchangeable.
• US data. SR Legacy records are US samples, not Indian averages, and IFCT 2017 has no seaweed row.
• Energy is calculated. USDA labels the kcal Calculated on every row; we print it as is.
• No cooked, flavoured or branded rows. Seaweed snacks, sushi, salads and noodles are not covered, and no maker's label is used.

How to log it so the numbers hold

• Weigh it, and say dried or raw. 7 g of dried spirulina (the USDA tablespoon weight) on SR Legacy 170495 is 290 × 7 / 100 = 20.30, so 20.3 kcal.
• Do not log dried as raw. A weight of dried spirulina logged against the raw row would carry about one eleventh of its energy.
• Add the rest of the dish separately. Oil, rice and sauces are in our other guides.

Where NYUS fits (our app)

We make NYUS, so read this as ours. NYUS is an AI fitness and nutrition coach in early access on Android, with no ads and no data selling. You log foods yourself by searching 8,900+ Indian and global foods or by barcode, and a weekly check-in adjusts your calories, macros and step goal once enough is logged. Barcode coverage of Indian packaged foods is not complete, so search by name when a scan finds nothing.

What this page leaves out

• A calorie target, and any claim about what seaweed or spirulina does to your body, including iodine, thyroid or heavy-metal questions: we have not looked up any for any person, so we give none. If you have a medical condition or are pregnant, ask your doctor or dietitian.
• Agar: the SR Legacy agar records (a dried and a raw row) are on our jelly, gelatin and agar guide, not repeated here.
• Seaweed snacks, sushi rolls, seaweed salads, kelp noodles and any maker's version: no row used here.
• Per-teaspoon, per-packet and per-sheet-of-snack figures: USDA prints none for these records, so we give none.
• Other SR Legacy rows that mention kelp, such as herring eggs on giant kelp (168989, a fish row), and Foundation foods records, which we did not search.
• Nutrients beyond energy, water, protein, fat, carbohydrate, fibre and sodium: not covered here.

Sources

• USDA FoodData Central, SR Legacy 170495 (Seaweed, spirulina, dried): Energy 290 kcal (1210 kJ), protein 57.5 g, total fat 7.72 g, carbohydrate 23.9 g, fibre 3.6 g, sodium 1050 mg per 100 g; kcal labelled Calculated; portions used: 1 cup (112 g); 1 tablespoon (7 g) (read 29 Oct 2026).
• USDA FoodData Central, SR Legacy 170091 (Seaweed, spirulina, raw): Energy 26 kcal (109 kJ), protein 5.92 g, total fat 0.39 g, carbohydrate 2.42 g, fibre 0.4 g, sodium 98 mg per 100 g; kcal labelled Calculated; portions used: none printed (read 29 Oct 2026).
• USDA FoodData Central, SR Legacy 168458 (Seaweed, laver, raw): Energy 35 kcal (146 kJ), protein 5.81 g, total fat 0.28 g, carbohydrate 5.11 g, fibre 0.3 g, sodium 48 mg per 100 g; kcal labelled Calculated; portions used: 10 sheets (26 g); 2 tbsp (1/8 cup) (10 g) (read 29 Oct 2026).
• USDA FoodData Central, SR Legacy 170496 (Seaweed, wakame, raw): Energy 45 kcal (188 kJ), protein 3.03 g, total fat 0.64 g, carbohydrate 9.14 g, fibre 0.5 g, sodium 872 mg per 100 g; kcal labelled Calculated; portions used: 2 tbsp (1/8 cup) (10 g) (read 29 Oct 2026).
• USDA FoodData Central, SR Legacy 168457 (Seaweed, kelp, raw): Energy 43 kcal (180 kJ), protein 1.68 g, total fat 0.56 g, carbohydrate 9.57 g, fibre 1.3 g, sodium 233 mg per 100 g; kcal labelled Calculated; portions used: 2 tbsp (1/8 cup) (10 g) (read 29 Oct 2026).
• USDA FoodData Central, SR Legacy 168456 (Seaweed, irishmoss, raw): Energy 49 kcal (205 kJ), protein 1.51 g, total fat 0.16 g, carbohydrate 12.3 g, fibre 1.3 g, sodium 67 mg per 100 g; kcal labelled Calculated; portions used: 2 tbsp (1/8 cup) (10 g) (read 29 Oct 2026).
• USDA FoodData Central, SR Legacy 167602 (Seaweed, Canadian Cultivated EMI-TSUNOMATA, dry): Energy 259 kcal (1080 kJ), protein 15.3 g, total fat 1.39 g, carbohydrate 46.2 g, fibre 36.7 g, sodium 4330 mg per 100 g; kcal labelled Analytical (water, protein, fat, fibre, sodium); Calculated (kcal, kJ, carbohydrate by difference); portions used: 0.25 cup (5 g) (read 29 Oct 2026).
• USDA FoodData Central, SR Legacy 167603 (Seaweed, Canadian Cultivated EMI-TSUNOMATA, rehydrated): Energy 31 kcal (132 kJ), protein 1.86 g, total fat 0.17 g, carbohydrate 5.62 g, fibre 4.5 g, sodium 526 mg per 100 g; kcal labelled Analytical (water, protein, fat, fibre, sodium); Calculated (kcal, kJ, carbohydrate by difference); portions used: 0.25 cup (25 g) (read 29 Oct 2026).
• ICMR-NIN, Indian Food Composition Tables 2017 (IFCT 2017): no seaweed, spirulina, laver, wakame or kelp row (PDF text searched 29 Oct 2026), so IFCT 2017 is not used on this page.
• nyus.in, the NYUS landing page, read on 29 Oct 2026 for the app statements in the NYUS section and the CTA.

The portion kcal, the sums, the rounding, the comparisons and every sentence starting "Our reading" are NYUS's own arithmetic or opinion, not from USDA. The energy, water, protein, fat, carbohydrate, fibre and sodium values and the printed portions are exactly as shown on the USDA record pages. The names in the first column are USDA's own record names.

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