Best Fat Burners 2021
Our guide to some of the leading Fat Burning supplements on sale
Last updated: 16th February 2021

This is our expert guide to the best fat burners on the market. These popular food supplements (typically made from plant extracts) aim to help transform the way you look and feel. Remember, there’s no such thing as a magic pill. But alongside a healthy diet and exercise regime, the best products could help you achieve your goals in less time.
The current fat burning supplement market is a competitive one, with many products claiming to be the ‘best’. And we understand if you’re finding it tough to make sense of it all. We’ve scoured the web, cut through the marketing hype and reviewed our best product picks for 2021 below.
- Cut through the hype
- Make the right choice for you
- Achieve your goals faster
Our top picks for 2021

- Natural ingredients
- Endorsed by MMA athletes
- Popular across the globe
- Money-back guarantee

- Designed for busy men
- Said to burn fat, not muscle
- Premium, natural ingredients
- No artificial colors or fillers

- Works well for men
- Powerful ingredients
- Blocks hunger
- Vegan friendly
Legion Athletics Phoenix

- Natural ingredients
- Caffeine-free
- Said to reduce hunger and cravings
- No milk or eggs

- Enhances exercise plans
- Natural formula
- Vegan-friendly caps
- Allergen-free
Full reviews
Knowledge is key – take an in depth look at our reviews below
Overview
Instant Knockout is one of the most popular supplements you’ll find online in 2021. The internet is flooded with positive reviews and customer testimonials vouching for the quality of the formula. Most reviewers say it works best as part of a healthy workout and nutrition plan.
Sold as a capsule rather than a powder, Instant Knockout boasts happy customers all over the world and continues to grow in popularity.
Like a lot of supplements, these capsules are aimed at bodybuilders and athletes. But search for reviews online, and you’ll see that men of all shapes, sizes and walks of life love Instant Knockout.

What’s in it?
Instant Knockout contains green tea and cayenne pepper – both staples of many popular fat burners. These ingredients are said to help burn more calories, which could lead to faster results. IK also contains glucomannan, a fiber which may promote fullness and reduce food cravings. These ingredients are joined by vitamin B6 and B12, GTF chromium, zinc, piperine and green coffee extract. The result? A natural supplement without any risky substances – and one that could help you achieve your goals faster.
How to take it
Each bottle of Instant Knockout contains 120 capsules. According to the manufacturer’s instructions, you’ll get best results by taking it four times a day – once in the morning, lunch, in the afternoon and before your evening meal.
- Produced in cGMP and FDA-approved facilities
- Packed with natural ingredients at optimal doses
- Positive reviews from experts and customers
- Vegan friendly
Conclusion
Instant Knockout looks great – but all the signs suggest it offers much more than pretty packaging. The product can help support your training goals, boost confidence and keep you motivated for longer as part of a good diet and exercise routine. No proprietary blends and transparent formula are big bonuses and make this product stand out on our list!

at instantknockout.com

Hunter Burn
Overview
Hunter Burn is described as a ‘premium’ fat burner. It’s aimed at the top end of the market and is designed for those looking for larger doses and higher quality ingredients. This comes at increased cost – but does it deliver? Hunter Burn features the largest serving sizes we’ve ever seen, while also using more potent forms of certain key ingredients. Some will want the cheapest on the market. But this is a highly-researched formula for men who are happy to pay more to get the best.
What’s in it?
Hunter Burn contains the key ingredients you’ll find in other products, but at much higher doses. For example, it contains matcha green tea, a variant of the green tea extract you find in other products. The difference is this type of green tea is three times stronger – and (in theory) it could help burn calories even faster. Hunter Burn also contains konjac root, which is said to reduce hunger. To finish off, a good dose of vitamin D3 is thought to help you lose weight, but gain muscle. The larger servings make up for the high price, giving you a range of meticulously-researched ingredients in optimal amounts.
How to take it
Each daily serving is six capsules, and there are 30 servings per container, giving you a month’s supply. The directions on the label state that you should take two capsules with a large glass of water three times a day before your main meals. As with any supplement, you’ll need to take it for a couple of months alongside a healthy fitness program and diet to give your body time to adjust. If you have any pre-existing conditions, remember to seek medical advice before taking any supplements.
- Higher doses for maximum impact
- Natural and safe ingredients
- Looks & feels premium
- Only available direct from the manufacturer
- High price point
Conclusion
As with any supplement, you need to make sure the ingredients are safe, natural, carefully selected and in the right amounts. Hunter Burn seems to meet these criteria and even though it costs a bit more, you seem to get what you pay for. A supplement for those who are quality conscious.

at hunterlife.com

Hourglass
Overview
Third on our best fat burners list is Hourglass Fit, a 120 capsule fat burner which has an impressive selection of ingredients and attractive looking packaging. You might be put off by some of the more female orientated aspects of the product, including the marketing and the look of the brand, but don’t be. There’s no such thing as a gender specific fat burner. Men and women’s bodies are almost identical so there’s no reason why this product won’t work for any man. The best way to prove this is to look at the ingredients. As you’ll see, they’re common in many male targeted fat burners.
What’s in it?
Hourglass Fit contains a great ingredient portfolio, enough to stand out against many of the market leading fat burners. For instance, you’ll find a generous dose of glucomannan, a root extract that swells when it hits your stomach and stops you from getting annoying hunger cravings between meals[1]. As well as this, your appetite is kept well under control with the addition of 5-HTP. This compound is known as a natural precursor to serotonin, a brain chemical which has been shown to offset hunger-inducing hormones, helping you control your food intake[2].
Also inside is cayenne pepper, a known thermogenic that works to heat up your body, boost your metabolism and help you burn more calories in less time[3]. It also contains a range of vitamins including zinc, vitamin B6, and vitamin B12. In addition, black pepper extract ensures your body absorbs the other vital nutrients in the formula.
[1] https://www.ncbi.nlm.nih.gov/pubmed/16320857
How to take it
Each bottle contains 120 capsules, giving you plenty of fat burning pills for a calendar month. To get the best effect you should take one capsule four times a day.
- Completely natural formula
- Works perfectly for men
- Suitable for vegans
- Potent appetite suppressants
- High quality production
- Only available direct from the manufacturer
Conclusion
Hourglass Fit is a great choice for a men’s fat burner, despite being marketed at women. Ignore the packaging and look at the list of ingredients and the product. It’s clear to see the creators have put a lot of thought into this supplement, even making the capsules vegan friendly. The ingredients complement each other perfectly to target every aspect of the weight loss process.
One thing to note is that Hourglass Fit doesn’t contain any stimulants. If you struggle with motivation levels when on a low-calorie diet, the absence of a stimulant may mean Hourglass Fit won’t work for you. However, if you are sensitive to stimulants, you’ll likely get on with this supplement very well. Overall, Hourglass Fit is a fantastic product with a top selection of ingredients and we’d highly recommend it for anyone serious about buying a fat burning supplement in 2021.

at hourglassfit.com

Legion Athletics Phoenix
Overview
Legion Athletics Phoenix is described by the manufacturer as “a 100% natural, caffeine-free fat burner”. It may help you burn fat by reducing hunger cravings and speeding up your metabolism, while also offering to raise your energy levels. In a video on the brand website, the founder states that this product could help “drive fat loss with proper dieting”. To his credit, the founder also states that Legion Phoenix will only help you achieve optimal results when you use it as part of a healthy exercise and diet plan.
What’s in it?
In this nine-ingredient formula, you will find naringin – a flavonoid said to improve lipid metabolism and fight obesity. It also features epigallocatechin gallate (ECGC), an active ingredient of green tea that has been shown to increase weight loss. Meanwhile, 5-HTP is thought to improve mood and reduce the appetite, and L-tyrosine could improve your ability to focus under the stress you may feel when cutting calories. In addition, hesperidin is said to help fight inflammation – a possible cause of weight gain, and forskolin may also help prevent obesity.
How to take it
Take three capsules with breakfast. Then, take another two capsules with either lunch or dinner. For best results, the manufacturer recommends combining Phoenix with caffeine.
- 100% natural
- Caffeine-free
- May reduce hunger cravings
- Some ingredients not as well-researched
- Must combine with caffeine for best results
Conclusion
Legion Athletics Phoenix is a very good product – and it checks most of the boxes you need from a weight-loss product. We’re not fans of ingredients like salicin, which lack the research you’d expect from a fat burner of this quality. However, Phoenix does contain ingredients which could deliver most – if not all – it promises.

Overview
From the Sport range at Performance Lab is a Sport Fat Burner which aims to improve your training and muscle building goals. It claims to give you the ability to train at a higher intensity and greater endurance at the gym. Sport Fat Burner allegedly does this by working well when combined with a fasted exercise plan.
What’s in it?
Performance Lab Sport contains several quality ingredients including coleus forskohlii, cayenne pepper extract, black pepper extract and the ‘featured nutrient’ beta-hydroxy beta-methylbutyrate (HMB). HMB is purported to neutralize enzymes that cause muscle damage when in the gym, boost hypertrophy and improve strength gains. All combined, these ingredients could help you acheive your training goals. Though you need to make sure you’re exercising regularly or eating well, as no supplement is a remedy for a bad diet and inactivity.
How to take it
Performance Lab recommend you take two to four capsules per day. They say you should take your capsules 15 minutes before you hit the gym. As with any supplement, you’re advised to see your physician before taking it, especially if you’re taking any other medication or have any long-term medical problems.
- Designed with training and exercise in mind
- Natural & thoroughly researched
- Vegan friendly capsules
- Only available direct from the manufacturer
- High price point
Conclusion
Performance Lab Sport Fat Burner is a great option for those who want a supplement to complement their hard work in in the gym who do not want to compromise on quality.