A typical 2 tbsp serving of kelp contains 0.2 grams of protein (1.68 g per 100 g), which makes it only a minor source of protein. That covers roughly 0% of the 50 g reference Daily Value, so it adds toward your protein total for the day.
Around 16% of the calories in kelp come from protein, so it is more of an energy food than a protein food. It contributes to a day's protein total, but the bulk of what it delivers is energy rather than amino acids - treat it as a contributor alongside a denser source, not as the protein in a meal.
Among the 105 vegetables in the database, kelp ranks 102nd by protein per serving, and 790th out of all 796 foods on the site. Set against eggplant, another vegetable entry in the database, a serving carries about 0.6 g less protein (eggplant has 0.8 g per 1 cup cooked).
It is an incomplete protein on its own; pairing it with other plant foods across the day covers the full range of essential amino acids. The serving above is measured by volume at 10 g. The per-100 g figure lets you compare it directly against any other food here, whatever its serving.
Source: USDA FoodData Central #168457 - "Seaweed, kelp, raw" (SR Legacy, published 4/1/2019). Values are the published reference figures for that record, not lab measurements for a specific brand or batch.
Quick answers
Kelp protein FAQ
How much protein is in kelp per 100 g?
Kelp has 1.68 g of protein per 100 g. A typical 2 tbsp serving (10 g) provides 0.2 g.
Is kelp a complete protein?
No. Kelp is an incomplete protein on its own; pairing it with other protein sources across the day covers the full range of essential amino acids.
How much of the Daily Value does a serving of kelp cover?
A 2 tbsp serving of kelp contains 0.2 g of protein, about 0% of the 50 g reference Daily Value.
Is kelp a good source of protein?
Kelp is only a minor source of protein, and about 16% of its calories come from protein, which makes it more of an energy food than a protein food. Set against eggplant, another vegetable entry in the database, a serving carries about 0.6 g less protein (eggplant has 0.8 g per 1 cup cooked).