How to Gain Weight Fast as a Skinny Guy: The Hardgainer Guide

For our overall top picks, see the Best Mass Gainer in Australia guide.

To gain weight fast as a skinny guy, eat about 300 to 500 Calories more than you burn every day and lift weights three to four times a week, so most of the gain is muscle rather than fat. Aim for about 1.6 to 2.2 g of protein per kg of body weight a day and a steady gain of about 0.25 to 0.5% of your body weight a week. If you struggle to eat enough, a mass gainer shake is the easiest way to add calories, and creatine monohydrate helps you get stronger in the gym. Here is the full plan, with a sample day of eating.

The hardgainer plan at a glance

These targets come from a 2019 review of nutrition for natural lifters building muscle by Iraki and colleagues. That may sound slow, but it still adds up to several kilos over a year, and more of it is likely to be muscle than if you gain as fast as you can.

Step 1: eat more, every day

• Add 300 to 500 Calories a day to what you eat now. Weigh yourself at the same time each week. If your weight has not moved after two weeks, add another 200 to 300.
• Eat four to five times a day. Smaller, more frequent meals are easier than three huge ones when your appetite is small.
• Drink some of your calories. A shake made with milk is far easier than another plate of food.
• Choose energy-dense foods: rice, oats, pasta, bread, nut butters, full-cream milk, olive oil, cheese, eggs and meat.
• Eat the same on rest days. Your body builds muscle on the days you do not train too.

A simple day of eating for a 65 kg hardgainer

That is about 3,500 Calories (about 14,600 kJ), with every figure except the shake being a rough estimate. Adjust it up or down based on your weekly weigh-in. For more meal ideas, see our bulking diet plan.

Step 2: hit your protein and lift heavy

The same review suggests 1.6 to 2.2 g of protein per kg of body weight a day while you are building muscle, spread over three to six meals. The ISSN gives a similar range of 1.4 to 2.0 g per kg for most people who exercise. For a 65 kg lifter, that is roughly 105 to 145 g a day. A scoop of R1 Whey Blend adds 24 g. Read our protein per day guide for more.

Training is what turns extra food into muscle. Lift three to four days a week and build your sessions around big lifts such as squats, deadlifts, bench press, rows and overhead press. Add a little weight or a rep or two over time. Keep cardio light while you are bulking. Without lifting, most of the extra calories end up stored as fat. Need a program? Start with our workout plans.

Step 3: use supplements to make it easier

No supplement is required, but the right ones make a surplus much easier to hit. Mass gainers work because they add calories and protein in a drink, not because of any special ingredient.

You do not have to take a full serve. Half a serve of a big gainer is often the right place to start, and you can build up from there. CBUM Mass Gainer is one of our best sellers in the last six months, and at the time of writing it works out to about $7.00 per full serve. CBUM, Serious Mass and Mass Tech Extreme also include some creatine per serve (2.5 to 3 g on the labels).

If you can already eat big meals and just need more protein, a whey shake is enough. Creatine monohydrate is worth adding either way: it is in Group A of the AIS Sports Supplement Framework, and 3 to 5 g a day helps you lift more over time. Legit Creatine Monohydrate 500 g gives you 100 serves for $49.95. Creatine also adds a little water to your muscles, so expect the scale to move a bit in the first month.

Common mistakes

• Eating big on training days and too little on rest days. Your weekly average is what counts.
• Lots of cardio and no strength training. You will burn the surplus and build little muscle.
• Chasing the scale too fast. Gaining much faster than about 0.5% of your body weight a week usually means a bigger share of fat.
• Relying only on shakes. Use them to top up meals, not replace them.
• Not tracking. Weigh yourself weekly and adjust. Guessing is why many hardgainers stall.

If you have always struggled to gain weight, have very little appetite, or are losing weight without trying, see your GP first to rule out a medical cause.

Our verdict

Gaining weight as a skinny guy comes down to a steady calorie surplus, enough protein and heavy lifting, done every week. Supplements make it easier, not automatic. If you find big meals hard, start with half a serve of CBUM Mass Gainer or a full serve of R1 Clean Gainer once a day, and add creatine monohydrate.

Compare more options in our best mass gainer in Australia guide, or browse all weight gainers. For a closer look at the big three, read CBUM vs Serious Mass vs Mass Tech Extreme.

How our price compares

Here is what the same products cost at other Australian supplement stores, so you can check the difference yourself.

Supps247 prices come from our website. Other prices were checked on the websites of Nutrition Warehouse, Australian Sports Nutrition (ASN), Elite Supps and Supplement Mart on 29 October 2026 (same product and size, price for one unit) and can change at any time. Sale means it was on sale that day. Some flavours means that price was for some flavours only. Out of stock means it was listed but not available that day. Not listed means we could not find that exact product on their site. Other sizes only means they sell it in a different size. Supps247 members can use our Price Match Guarantee against Nutrition Warehouse, ASN, Elite Supps and Supplement Mart: we beat their full price by 5% or match their sale price (conditions apply).

Shop the products in this guide

CBUM Mass Gainer 12 lb$139.95R1 Clean Gainer 15 serves$119.95ON Serious Mass 5.46 kg$169.95Legit Creatine Monohydrate 500 g$49.95

Browse all weight gainers.

FAQs

How can a skinny guy gain weight fast?

Eat about 300 to 500 Calories more than you burn every day, lift weights three to four times a week, and get about 1.6 to 2.2 g of protein per kg of body weight. A mass gainer shake makes the extra calories easier. Aim for about 0.25 to 0.5% of your body weight a week, so more of the gain is muscle rather than fat.

Do mass gainers work for hardgainers?

Yes, as a convenient way to add calories and protein. They work because a shake is easier to get down than another meal, not because of any special ingredient. Start with half a serve if a full one is too much, and keep eating proper meals. Check the serve size on the label, as some gainers list more than 2,000 Calories per full serve.

Should I take creatine to gain weight?

Creatine monohydrate helps you lift more over time, which supports muscle gain when you train, and it adds a little water to your muscles. The AIS lists it in Group A of its Sports Supplement Framework. Take 3 to 5 g a day with water or a shake. It is not a weight gainer on its own, so you still need to eat in a surplus.

How much weight should I gain per week?

A 2019 review suggests about 0.25 to 0.5% of your body weight a week for beginner and intermediate lifters. For a 65 kg lifter, that is roughly 0.15 to 0.3 kg a week. If you gain faster than that, a bigger share is likely to be fat. Weigh yourself once a week at the same time and adjust your food if you stall.

What if I have no appetite?

Eat smaller meals more often, drink some calories as shakes or milk, and lean on energy-dense foods like oats, nut butters, rice and olive oil. Eating at set times helps too. If you have always had a very small appetite or are losing weight without trying, see your GP to rule out a medical cause before you push harder.

Sources: Iraki and colleagues (2019), nutrition recommendations for bodybuilders in the off-season; ISSN protein and exercise position stand (2017); ISSN creatine position stand (2017); AIS Sports Supplement Framework; product labels and brand nutrition panels, checked October 2026.

Order online with Australia-wide delivery, free on orders of $99.99 or more, with Afterpay available at checkout. You can also use click and collect at a store that offers it, or visit a Supps247 store in Melbourne, regional Victoria or Brisbane to compare products in person. Members can use our member price match on full-priced items.

Prices and stock were checked on 29 October 2026 and can change at any time. Always read the label and follow the directions for use. If you have a medical condition, are pregnant or take regular medication, check with your doctor first.