The Best Vitamin D Supplements of 2025: How to Choose and More

We worked with a certified nutrition coach to test and select five science-backed vitamin D supplements that fit demanding lifestyles and health goals. Whether your aim is to stay ahead at work, bolster your resilience, or simply maintain peak daily performance, we’ve got your vitamin D needs covered in 2025.

Why Trust Fortune

Our team of expert testers has tried hundreds of the most popular supplements on the market today, using our comprehensive supplement testing methodology to find the best products for all folks.  

Best Vitamin D Supplements of 2025

• Best Vitamin D Supplement Overall: Transparent Labs Vitamin D3 + K2
• Best Vitamin D K2 Supplement: Nutricost Vitamin K2 + Vitamin D3
• Best Vitamin D Supplement for Women: Thorne Vitamin D
• Best Vitamin D Supplement for Men: Now Vitamin D3
• Best High Dose Vitamin D Supplement: Sports Research Vitamin D3

Best Vitamin D Comparison Table

Best Vitamin D Supplement Overall: Transparent Labs Vitamin D3 + K2

Our Thoughts on Transparent Labs Vitamin D3 + K2

Transparent Labs Vitamin D3 + K2 is our pick as the best overall vitamin D supplement because it pairs two highly effective nutrients, both essential to optimal health, in their most absorbable forms. With a vegan, allergen-free formula, rigorous third-party testing, and a dosage that meets the needs of those with above-average requirements, it offers a premium, science-driven solution. 

Pete tested this supplement and rated his first impression of the product a 5 out of 5. “This supplement comes in a white plastic bottle with a smooth screw-top lid that opens and closes easily,” he said. “The white label has navy and black lettering that’s easy to read. All key product details are clearly displayed, and the inclusion of the Informed Choice certification is shown on the front of the label.”

He found the directions straightforward and easy to follow: “It says to take one softgel one to two times a day with a meal containing fats,” Pete said, rating the instructions a 5 out of 5. While the specification that the meal contain fats might seem inconvenient, vitamin D is a fat-soluble vitamin, which means it’s best absorbed with fats, so there’s a solid reason behind the instructions. Our tester also liked that Transparent Labs’ softgel capsules are small and easy to swallow, especially considering it’s only one capsule per serving. 

Our tester didn’t experience any taste when testing this supplement, nor did he have any side effects, rating it a 5 out of 5 in this category. Overall, Pete was pleased that Transparent Labs advises taking the softgel with a meal that contains dietary fat to support proper absorption. “This supplement is a solid option for anyone looking to boost or maintain higher vitamin D levels, especially if they don’t get a lot of sun exposure, such as during the winter months. I also like that the product is third-party tested, which adds an extra layer of trust and transparency,” he said.

Best Vitamin D3 K2 Supplement: Nutricost Vitamin K2 + Vitamin D3

Our Thoughts on Nutricost Vitamin K2 + Vitamin D3

Nutricost’s Vitamin K2 + Vitamin D3 is our pick for the best combination K2 and D3 supplement thanks to its clinically effective dosages of both nutrients, excellent value, and trusted third-party testing for safety and efficacy. By providing 5000 IU of D3 and 100 mcg of K2 (MK-7) in a single, easy-to-swallow daily softgel, it addresses two of the most crucial vitamins for bone density and cardiovascular function.

Kate tested this vitamin D supplement, rating her first impression of the product a 5 out of 5. “The bottle has typical Nutricost branding. It is very clearly labeled and easy to understand what the product is,” she said. It’s a regular twist-off bottle, so she found it super easy to open and close. “The bottle isn’t as small as some of the other vitamin D bottles I’ve tested, but it could still fit in a larger purse or backpack,” she said.

She rated swallowability a 5 out of 5, saying: “These softgels are very tiny! They are smaller than penny. They were very easy to swallow, and since I only had to take one, I had no issues with it!”

Kate did notice a bit of a taste to these softgels, rating that factor a 3 out of 5. “You can really smell the softgels when you first open the bottle–they smell and taste a bit funky. It’s not overwhelming at all, especially since the softgels are so small,” she said. This didn’t bother Kate, but it could bother folks who are sensitive to taste and smell when taking a supplement.

Our tester didn’t experience any side effects after taking this supplement. Overall, Kate thinks this is a great neutral product for someone who is looking to increase their vitamin D intake. “It’s cost efficient and reviewers didn’t seem to have many, if any, side effects from it,” she said.

Best Vitamin D Supplement for Women: Thorne Vitamin D

Our Thoughts on Thorne Vitamin D

Thorne Vitamin D is our pick for the best vitamin D supplement for women because of its research-driven formula: It provides highly absorbable vitamin D3 paired with vitamin E, an antioxidant that studies show is often lacking in women’s diets. In one study, nearly 90% of women of reproductive age had inadequate vitamin E intake, while another found that 96% of women in the U.S. are at risk for low vitamin E—especially those who avoid high-fat foods or lack nuts, seeds, and healthy oils in their diet.

Kate tested this supplement, rating her first impression of the product a 5 out of 5. “I love Thorne’s packaging–it’s sleek. The bottle is a simple twist-off and I had no issues opening it up. The bottle is small, it’s only about the side of a saline spray bottle, which makes it easy to transport and carry around daily,” she said.

She rated swallowability a 5 out of 5, praising the small size of the softgels: “These pills are an amazing size. They’re about half the size of a typical supplement capsule, only about as long as my pinky nail and about half the width,” she said. “It was super easy to swallow. You only need to take one, so I would even take this directly with my other vitamins as it didn’t take any effort to swallow,” Kate said.

Our tester didn’t notice any taste or smell to this vitamin D supplement and was pleased to note that this is unlike her experience with some other vitamin D pills she’s tried. Kate rated it a 5 out of 5 for taste. 

Overall, she thinks this is a good product for someone who wants to grab and take the bottle with them on the go. “It has foundational vitamin D properties along with immune support and bone support. It has some additional benefits, which could be great if you are looking for additional support from your vitamin D supplement.”

Best Vitamin D Supplement for Men: Now Vitamin D3

Our Thoughts on Now Vitamin D3

NOW Vitamin D3 is our pick for the best vitamin D supplement for men based on its moderate dose, broad benefits, and excellent value. Vitamin D3 supplementation is critical for men, not only for immune and bone health but also for maintaining muscle strength, regulating testosterone, and improving mood and cardiovascular function. NOW stands out for its rigorous quality standards and allergen-free formulation, too.

Kate tested this supplement, finding the instructions super easy to follow, giving them a 5 out of 5 rating. This tester also noted how tiny the pill is, rating swallowability a 5 out of 5 as well. “The tiny little softgels are super easy to swallow and are a transparent orange color. You only need to take one softgel, which is great for anyone who doesn’t like to swallow pills,” she said.

She did have to give the product packaging a 3 out of 5, though, noting that the label is a little busy and the text is small, which may not be easy for everyone to use. “The color scheme makes it a bit hard to read, especially if you have any kind of colorblindness,” she said. “I also found opening the bottle to be not as simple as a twist-off, as you must rip off the plastic seal (kind of like a squeezy water bottle) but that wasn’t obvious. Once I got it the first time it became easier, but there was a bit of confusion for me initially.”

The softgels do have a “fishy and earthy smell” and Kate noticed that it tasted sour in her mouth, however she noticed zero aftertaste. “There was no aftertaste, which made it very tolerable,” she said. She recommends swallowing the softgel quickly with water and avoiding smelling the bottle. That said, since you’ll be taking this a fat-rich food, you likely wouldn’t notice any taste at all from the supplement. 

Best High Dose Vitamin D Supplement: Sports Research Vitamin D3

Our Thoughts on Sports Research Vitamin D3

Sports Research Vitamin D3 stands out as the best high-dose supplement due to its exceptional potency, ease of use, and quality assurance. Our tester tried the 5,000 IU softgel, which required just one pill per day, but the 10,000 IU version is identical in appearance and taste—still one softgel daily, making it a simple switch if a higher dose is needed. We love the inclusion of organic coconut MCT oil for enhanced absorption, and the product is non-GMO and third-party verified. We recommend talking with your doctor before starting any supplement, but especially if you are considering a high potency supplement such as this one.

Kate tested this supplement, rating her first impression of the product a 5 out of 5. “The Sports Research branding is great: the black matte bottle with a flip top is appealing both visually and when opening the bottle,” she said. “It’s very easy to tell what the product is, and its clearly labeled in white font.” However, Kate noted that this is the largest bottle out of all the vitamin D she’s tested, and is not travel-friendly.

Our tester rated the swallowability a 5 out of 5, praising how small the pill is. “It’s smaller than my pinky nail, which made it super easy to swallow. It is a softgel, which added to the comfort when taking it. It has a clear, yellowish tint to it and is striking against the black container, which I enjoy. You only need to take one softgel per day, so it is very easy to consume,” she said.

Kate found the smell and taste to be slightly fishy but still rated it a 5 out of 5 in this category. “It tastes a bit sour when it sits on your tongue, but the taste quickly goes away once you swallow the softgel with water. I didn’t notice an aftertaste at all,” she said.

Overall, she thinks this is a good product to take for a cost efficient and large dose of vitamin D. “Since it’s extra strength, it’s important to check with your doctor to see if this is the right dosage and product for you due to possible side effects,” Kate said. She loves that you get nearly a year’s supply in one bottle, 360 servings, for only $17.95.

What is a Vitamin D Supplement?

A vitamin D supplement is a product designed to help you meet your daily vitamin D needs, especially if you cannot get enough from sunlight or diet alone. It supports bone health, immune function, and overall wellness by providing a concentrated source of vitamin D in convenient pill, capsule, powder, or liquid forms.

Forms

Vitamin D supplements come in two primary forms: vitamin D2 (ergocalciferol), derived from plants and fungi, and vitamin D3 (cholecalciferol), synthesized from animal sources or produced naturally in your skin by sunlight exposure. Vitamin D3 is generally considered the more effective form for raising and maintaining blood vitamin D levels, while D2 may be preferred for a vegan lifestyle.

How We Tested and Selected the Best Vitamin D Supplements

When choosing top vitamin D supplements, we collaborated closely with a Registered Dietitian (RD) to ensure our testing focused on safety, effectiveness, and clinical backing. Formulas selected provide at least 100% of the recommended daily value (RDV) for vitamin D, and each product avoids artificial sweeteners, colors, and unnecessary additives.

Formula

Partnering with an RD strengthens our commitment to finding supplements with clinically supported dosages and thoughtful ingredient profiles. Specific to vitamin D, we select formulas that guarantee at least 100% RDV and steer clear of artificial ingredients.

Swallowability

We prepare each vitamin D product according to the manufacturer’s instructions and pay attention to how well the product dissolves, especially with powders. Avoiding gritty textures and off-putting taste ensures a better experience for routine daily use.

Third-Party Testing

Our team prioritizes products with third-party testing, such as NSF or USP certification. Third-party testing means the product has been independently analyzed for accuracy and purity, reducing the risk of contaminants or mislabeling. Since the FDA does not regulate most supplements as strictly as medications or foods, outside verification is crucial for consumer safety.

Value

In our evaluation process, we balance effectiveness, safety, ingredient quality, swallowability, and price to determine best-value vitamin D supplements. This approach ensures you get the most reliable product for your investment.

How to Find the Best Vitamin D Supplements for You

Vitamin D is essential for bone health, immune function, and muscle performance, but many people struggle to get enough from sunlight or diet alone. Supplements can help bridge the gap, but the best option depends on your individual needs and goals.

Your Fitness Goals

Athletes and active individuals have unique vitamin D requirements compared to the general population. For example, runners may focus on bone strength for injury prevention, while strength athletes might emphasize muscle function and recovery. Knowing your specific fitness goals—whether it’s improving performance, reducing injury risk, or supporting recovery—can help guide your search for the right supplement.

Formula

Before purchasing a vitamin D supplement, review ingredient lists to check for allergens or additives that could interact with your dietary preferences or restrictions. Some formulas offer vitamin D2 (ergocalciferol), while others provide vitamin D3 (cholecalciferol), which is generally more effective at raising blood vitamin D levels. 

Cost

Supplements range in price, and cleaner formulas with fewer fillers are often more expensive. Investing in a quality supplement can pay off in the long run if you plan to use it daily. Weigh cost against quality—higher prices usually reflect better sourcing, purity, and potency, which can be particularly important for something you’ll be taking regularly.

Third-Party Testing

Prioritize supplements that have been tested by independent, third-party organizations (such as NSF or USP). This ensures the product contains what it claims, is free of harmful contaminants, and meets quality standards. For serious athletes, third-party certification can also provide reassurance that the product is free from banned substances.

Benefits of Vitamin D Supplements

Vitamin D delivers several performance and health benefits, especially for people at risk of deficiency or those with increased needs due to high training loads:

• Helps maintain strong bones, reducing fracture risk. 
• Enhances muscle strength and supports better muscle function. 
• May reduce recovery time and injury risk in athletes. 
• Boosts immune system function, lowering rates of illness among athletes. 
• Contributes to reduced inflammation and improved mood.

How to Take Vitamin D Supplements

The optimal intake of vitamin D varies widely. General guidelines recommend 600 to 800 IU per day for most adults, but athletes, individuals with limited sun exposure, or those who are already deficient may need higher doses under medical supervision. 

Blood tests are the gold standard for assessing your vitamin D status—discuss supplementation with your doctor, particularly if you have specific health conditions or are on other medications. Common signs of vitamin D deficiency include fatigue, muscle weakness, bone pain, and frequent illness.

Can You Take Too Much Vitamin D?

Yes, taking too much vitamin D can be harmful. The tolerable upper intake level is typically set at 4,000 IU per day for adults, but toxicity is rare and usually associated with chronic intake of very high doses. Symptoms of vitamin D toxicity may include nausea, vomiting, weakness, and kidney problems. Always stick to dosing guidelines and talk with your doctor for personalized recommendations.

What to Avoid in Vitamin D Supplements

When picking a supplement, avoid:

• Excessive or unclear dosing 
• Products lacking third-party certification
• Artificial additives, fillers, or allergens that could pose health risks

Frequently asked questions

What is the most effective vitamin D to take?

Vitamin D3 (cholecalciferol) is generally considered the most effective form for raising and maintaining blood vitamin D levels.

What are the most common mistakes people make when taking vitamin D supplements?

Two of the most common mistakes people make when taking vitamin D supplements are: taking too little or too much without doing bloodwork first, and choosing poor-quality supplements without third-party testing.

Can vitamin D deficiency cause itchy rash?

Vitamin D deficiency is not a common cause of itchy rashes, but it can contribute to immune dysfunction, which may indirectly affect skin health. We recommend talking with your doctor if you are experiencing skin issues.