How much protein is in 1/2 cup rajma?

November 13, 2025 •

3 min read

According to the USDA, a 1/2 cup serving of cooked rajma, or kidney beans, typically contains around 7.5 to 9 grams of protein. This makes them an excellent, fiber-rich source of plant-based protein for vegetarians, vegans, and those looking to add more nutrition to their meals.

Quick Summary

A cooked half-cup of rajma provides a significant dose of plant-based protein, along with dietary fiber and other essential nutrients. The exact amount can vary slightly depending on preparation, but it remains a powerhouse legume for a healthy diet. It's a key ingredient for bolstering protein intake in vegetarian and vegan cuisines.

Key Points

Protein Content: A cooked 1/2 cup of rajma (kidney beans) provides approximately 7.5 to 9 grams of plant-based protein.
Cooked vs. Raw: The protein content per weight decreases during cooking due to water absorption, so measurements always refer to the cooked version.
Rich in Fiber: A single serving of rajma also offers a high amount of dietary fiber, which aids digestion and promotes satiety.
Complete Protein Meal: Pairing rajma with a grain like rice creates a complete protein source, supplying all essential amino acids.
Other Nutrients: Rajma is also a good source of vital minerals like iron, magnesium, and potassium, alongside folate.

Understanding the Protein in Rajma (Kidney Beans)

Rajma, known as kidney beans, is a staple in many cuisines worldwide, prized for its hearty texture and nutritional benefits. The protein content is a major draw, especially for those on plant-based diets. Knowing the protein quantity in a standard serving is essential for meal planning and meeting dietary goals.

Raw vs. Cooked: The Protein Shift

There is a notable difference in the protein concentration of raw versus cooked rajma due to the absorption of water during the cooking process. When you cook beans, they expand and take on a significant amount of water, which effectively dilutes the nutrients by weight. For example, 100 grams of raw rajma has a much higher protein density than 100 grams of cooked rajma. This is why nutritional information is almost always presented for the cooked weight of legumes. A half-cup serving is a common measurement for cooked beans, providing a realistic estimate of what you'll consume.

Nutritional Breakdown of a Half-Cup Serving

Beyond protein, a 1/2 cup of cooked rajma offers a wealth of other beneficial nutrients. This is what makes it a complete dietary addition, not just a protein source. Here is a more detailed look at the nutritional content based on approximate values:

Protein: ~8 grams
Fiber: ~7-8 grams
Carbohydrates: ~20 grams
Fat: ~0.5 grams
Folate (B9): Important for cell growth and metabolism
Iron: Crucial for transporting oxygen in the blood
Magnesium: Involved in hundreds of bodily processes
Potassium: Essential for heart function and blood pressure

How to Maximize the Protein from Rajma

To get the most out of your rajma, consider these preparation and pairing tips:

Complete the amino acid profile: While rajma is a great source of protein, it is not a 'complete' protein on its own. Pair it with a grain like rice, a staple combination, to ensure you get all the essential amino acids your body needs. This is the basis of many traditional recipes like rajma chawal.
Incorporate into diverse meals: Add rajma to salads, stews, chili, or mash it for a spread. Diversifying your use of rajma ensures you don't grow tired of it and makes it easier to incorporate into your regular diet.
Proper soaking and cooking: Always soak dried rajma for at least 8-10 hours before cooking. This not only reduces cooking time but also helps break down indigestible complex sugars (oligosaccharides), which can cause gas. A pressure cooker is an efficient way to ensure the beans are thoroughly cooked and soft.

Comparison: Rajma vs. Other Legumes (per 1/2 cup cooked)

Legumes are nutritional powerhouses, and rajma holds its own among them. Here is a comparison to illustrate how it stacks up against other popular choices:


Legume	Protein Content	Notes
Rajma (Kidney Beans)	~8 grams	A great all-rounder, very high in fiber.
Lentils	~9 grams	Slightly higher protein content; cooks much faster.
Black Beans	~8 grams	Similar protein to rajma, excellent source of antioxidants.
Chickpeas	~7.5 grams	Versatile for hummus and salads.
Soybeans	~14 grams	Significantly higher protein, a complete protein source.

The Health Benefits of Consuming Rajma

Eating rajma regularly offers several health advantages:

Supports Weight Management: The combination of high protein and fiber keeps you feeling full longer, reducing overall calorie intake.
Stabilizes Blood Sugar: Its low glycemic index means that rajma releases sugar into the bloodstream slowly, preventing spikes and crashes.
Promotes Heart Health: High fiber and nutrients like magnesium and potassium help manage cholesterol and regulate blood pressure.
Boosts Energy Levels: Rajma is rich in iron, which is essential for combating fatigue and boosting energy production.
Improves Gut Health: The prebiotic fiber in rajma feeds good gut bacteria, aiding digestion and enhancing nutrient absorption.

Conclusion: Your High-Protein Legume Choice

In conclusion, a 1/2 cup of cooked rajma provides a robust 7.5 to 9 grams of plant-based protein, making it an excellent addition to a balanced and healthy diet. Its combination of significant fiber, minerals like iron and magnesium, and slow-releasing carbohydrates contributes to weight management, blood sugar control, and overall well-being. By properly preparing and combining it with other food sources like rice, you can create a complete protein meal that is both nutritious and delicious. Whether you are vegetarian, vegan, or simply looking to incorporate more plant-based foods, rajma is a versatile and affordable option that should not be overlooked.

Frequently Asked Questions

No, rajma is not a complete protein on its own. While it provides a good amount of protein, it lacks certain essential amino acids. To create a complete protein meal, it should be paired with a complementary food like a whole grain, such as rice.

Yes, it is highly recommended to soak dried rajma for at least 8-10 hours before cooking. Soaking helps break down complex sugars that can cause gas and makes the beans easier to digest and cook evenly.

Canned rajma is a convenient option and still nutritious, typically offering a similar amount of protein per half-cup serving as home-cooked beans. However, they may contain added sodium, so it's wise to rinse them thoroughly to reduce the salt content.

To minimize gas, ensure you soak the rajma properly and cook it thoroughly. Adding spices known to aid digestion, like ginger, cumin, and ajwain, during the cooking process can also be very helpful.

Yes, rajma can be beneficial for weight loss. Its high fiber and protein content promotes feelings of fullness, which can help control appetite and reduce overall calorie intake.

The protein content per unit of weight is lower in cooked rajma than in raw rajma because the beans absorb water during cooking, effectively diluting the protein concentration. However, the total nutritional value remains intact.

When soaked and cooked thoroughly, rajma is a safe and beneficial food during pregnancy. It is rich in folate, iron, and protein, all of which are essential for maternal and fetal health.