A Deep Dive to Determine Which Brand of Citrulline is the Best?

October 4, 2025 •

5 min read

Studies indicate that L-citrulline supplementation is more effective at raising plasma arginine levels than arginine itself, leading to enhanced nitric oxide production. Determining which brand of citrulline is the best requires a close look at product form, purity, and testing standards to match individual performance goals.

Quick Summary

A guide to selecting the right citrulline supplement by comparing L-citrulline and citrulline malate based on scientific evidence. It details factors like third-party testing, dosage, and value, profiling reputable brands to help consumers make an informed choice for enhanced performance and recovery.

Key Points

Choose the Right Form: Decide between pure L-citrulline for focused nitric oxide enhancement and citrulline malate for potential additional energy (ATP) production via malic acid.
Verify Third-Party Testing: Look for certifications from independent organizations like Informed Sport or NSF to ensure purity, potency, and safety from banned substances.
Check the Ratio: If buying citrulline malate, a 2:1 ratio (2 parts citrulline to 1 part malate) is often preferred for higher active ingredient concentration.
Compare Value: Consider the cost per effective dose, not just the upfront price. Bulk powders from brands like BulkSupplements often offer the best long-term value.
Prioritize Transparency: Brands like Transparent Labs and Kaged stand out for providing transparent labeling and ingredient sourcing information.
Match to Your Goal: Pure L-citrulline may be sufficient for general blood flow benefits, while citrulline malate might be better for high-intensity or endurance athletes.

Understanding the Two Main Forms of Citrulline

When evaluating which brand of citrulline is the best, the first and most critical step is to understand the two main types available: L-citrulline and citrulline malate. While both aim to boost athletic performance, they have different compositions and nuances that can affect your results.

L-Citrulline: This is the pure, free-form amino acid. Your body efficiently absorbs L-citrulline, which is then converted to L-arginine in the kidneys to increase nitric oxide (NO) production. Increased NO levels lead to vasodilation, improving blood flow and oxygen delivery to muscles. This pure form is ideal if your primary goal is to maximize nitric oxide benefits without other ingredients.
Citrulline Malate: This form combines L-citrulline with malic acid, a natural compound found in fruits like apples. The malic acid is believed to play a role in the Krebs cycle, which is central to cellular energy production (ATP). Proponents suggest that this combination offers a dual benefit: improved blood flow from the citrulline and enhanced energy production and reduced fatigue from the malate.

The Importance of the Citrulline Malate Ratio

If you opt for citrulline malate, be aware of the ratio. The most common ratio is 2:1, meaning there are two parts L-citrulline for every one part malic acid. This is an important distinction because a higher ratio means a higher concentration of the active ingredient (L-citrulline) per dose. Some manufacturers may use a 1:1 ratio, which is less potent and often cheaper to produce, meaning you get less functional citrulline for your money.

Crucial Criteria for Choosing a High-Quality Brand

Beyond the type of citrulline, several factors determine a brand's overall quality and value. Focusing on these points will help you confidently choose a superior product.

1. Third-Party Testing and Transparency

Since supplements are not strictly regulated by the FDA, relying on a brand's own claims of purity is insufficient. Reputable brands voluntarily undergo third-party testing by independent labs like Informed Sport or NSF. This certification verifies that the product's ingredients match the label and, most importantly, are free from contaminants and banned substances. Brands that provide easy access to Certificates of Analysis (COAs) demonstrate a higher level of transparency and commitment to quality.

2. Ingredient Purity and Additives

The best citrulline brands often offer a single-ingredient product, especially for powders. This purity ensures you get exactly what you pay for without fillers, artificial colors, or unnecessary sweeteners. Simple, unflavored powders are often the most cost-effective and versatile option, as they can be mixed with other supplements or flavored beverages.

3. Effective Dosages and Value

Clinical studies on citrulline's effectiveness typically use specific dosages. For citrulline malate, 6–8 grams per serving is commonly cited for performance benefits. When comparing brands, always check the serving size and the number of servings per container to calculate the true cost per dose. A bulk powder from a trusted source is often the most economical option over time.

Comparison of Reputable Citrulline Brands


Brand	Form(s)	Key Feature	Third-Party Tested?	Typical Use Case
PureBulk	L-Citrulline DL-Malate (2:1), L-Citrulline	Best for bulk buying, low price per serving.	Yes.	Budget-conscious lifters and home formulators.
Transparent Labs	L-Citrulline (fermented), Citrulline Malate (2:1)	Superior transparency, third-party tested (Informed-Sport).	Yes.	Athletes prioritizing purity, transparency, and effective pre-workout blends.
BulkSupplements.com	L-Citrulline DL-Malate (2:1), L-Citrulline	Highly cost-effective bulk powders.	Yes.	Extreme value hunters, bulk supplement users.
NOW Sports	L-Citrulline (powder, capsules)	Consistent quality, wide availability.	Yes, tested in-house and third-party.	General fitness enthusiasts, those who prefer capsules.
Kaged Muscle	Fermented L-Citrulline	High-quality, plant-based, and fermented options.	Yes.	Athletes seeking clean, plant-based fermented amino acids.

Top Recommendations for the Best Citrulline Brand

Ultimately, which brand of citrulline is the best depends on your specific needs, budget, and priorities. The market offers excellent options for different types of consumers.

For the Quality and Purity-Focused Athlete: Transparent Labs and Kaged Muscle are top-tier choices. Both brands offer high transparency, use clean ingredients, and are rigorously tested by third parties. Transparent Labs provides an easy-to-search database for Certificates of Analysis, ensuring complete trust in their product. Kaged's fermented L-citrulline is a high-quality, plant-based option for those prioritizing clean sourcing.
For the Budget-Conscious User: BulkSupplements.com is a standout for value. Their no-frills, bulk powders provide the active ingredients at the lowest possible cost per serving, making them ideal for those who prefer to mix their own pre-workout stacks. While cost-effective, they still provide third-party testing.
For Convenience and Reliability: NOW Sports is a great all-around brand with a long history of quality and reliable products. They offer both powder and convenient capsule forms, making them a practical choice for everyday supplementation. Their consistent quality and third-party testing provide peace of mind.

How to Select Your Personal 'Best' Brand

To make your final decision, consider a few simple questions:

Form: Do you prefer the pure amino acid (L-citrulline) or the potential energy boost from malic acid (citrulline malate)?
Budget: Are you looking for the most cost-effective bulk powder, or are you willing to pay more for added convenience or a complex pre-workout blend?
Third-Party Testing: Is independent verification of purity and label accuracy a non-negotiable factor for you?
Other Ingredients: Do you want a clean, single-ingredient product, or a pre-workout formula with other performance enhancers?

By answering these questions, you can align your choice with the brands and product types profiled above.

Conclusion

There is no single brand that is universally the best for everyone, but by focusing on your specific goals and buying criteria, you can determine which brand of citrulline is the best for you. For most athletes seeking maximum performance benefits, a high-quality, third-party tested citrulline malate product in a 2:1 ratio is a strong contender. Brands like Transparent Labs and Kaged provide high purity and transparency, while bulk options from BulkSupplements.com offer excellent value. Regardless of your choice, prioritizing transparent and tested brands ensures you get a safe and effective product to support your fitness journey.

Choosing the Right Form and Brand

When selecting a citrulline supplement, your decision should weigh the purity of L-citrulline against the potentially synergistic effects of citrulline malate, keeping third-party testing as a top priority. For straightforward nitric oxide boosting, a pure L-citrulline powder or capsule from a reliable brand like NOW Foods is a great choice. For those seeking maximum performance enhancement, especially during intense workouts, a high-quality 2:1 citrulline malate from Transparent Labs or BulkSupplements offers both nitric oxide and potential ATP support.

A Final Word on Individual Results

It is important to remember that individual responses to supplements can vary. Some individuals may experience a more pronounced 'pump' or performance boost from citrulline malate, while others find pure L-citrulline sufficient. Monitoring your own body's reaction and adjusting your dosage and brand accordingly is key to finding the best fit for your unique needs. Always consult a healthcare professional before starting any new supplement regimen, especially if you have underlying health conditions or take other medications.

Frequently Asked Questions

L-citrulline is the pure amino acid, while citrulline malate combines L-citrulline with malic acid. The malic acid is believed to offer additional benefits for energy production, making citrulline malate a popular choice for enhancing endurance and reducing fatigue.

Both forms boost nitric oxide and blood flow, leading to a muscle 'pump'. However, because pure L-citrulline contains a higher concentration of the active amino acid per gram, some argue it is more effective for maximizing pumps. For overall workout performance, citrulline malate might offer a broader range of benefits.

In a 2:1 citrulline malate product, there are two parts L-citrulline for every one part malic acid. This ratio is generally favored over 1:1, as it provides a higher concentration of the performance-enhancing L-citrulline per dose.

Yes, third-party testing is crucial. Since supplements aren't tightly regulated, independent testing from bodies like Informed Sport or NSF verifies a product's purity and label accuracy, ensuring it is free from contaminants and banned substances.

For performance benefits, research often uses dosages ranging from 6 to 8 grams of citrulline malate, or slightly less for pure L-citrulline (e.g., 3 to 6 grams), taken about an hour before exercise.

You should not take citrulline if you are on blood pressure medication without consulting a doctor first. Citrulline can lower blood pressure and may lead to dangerously low levels when combined with other vasodilating drugs.

Pure, unflavored L-citrulline typically has very little taste and can be mixed easily into beverages. Citrulline malate, due to the malic acid, can have a noticeably tart or sour flavor.