How Long Does It Take a Chicken to Fully Grow? | The Ultimate Guide

Some can’t just get enough of the cute, fluffy chicks as they become mature in no time. Before you know it, the poultry is crowded, and you may not be prepared for it.

To avoid getting caught up, you have to be particular with the life cycle of the chicken and the necessary time for them to fully grow.

So, how long does it take a chicken to fully grow? It depends on the breed, but generally, it happens surprisingly fast. The chicks can be mature in 7 weeks and up to 18 months. The big gap is caused by deliberate breeding implementation.

Broilers are bred for a fast growth rate. They have a huge difference from the chickens almost a century ago in terms of genetics and physiological aspects.

Since these chickens are grown for meat, they can weigh 6.2 lbs in just 48 days. The chickens in 1925 were only 2.5 pounds after 112 days.

Of course, you’re only interested in the status quo of chicken growth. Since it depends on breed, you have to know the strain that you choose to raise. But the basic information in his article will also help you to develop your poultry.  

How Fast Do Chickens Grow to Full Size?

How Fast Do Chickens Grow to Full Size

Chickens like Cornish Cross chicken can be fully mature in just 7 weeks. On the other hand, Jersey Giant chickens are much bigger than broilers and are called a giant in the chicken world and need 18 months to reach full size.

It depends on the breed, but generally, chickens can grow to full size in 12 months.

How Long Does a Chicken Take to Grow Before Slaughter?

How Long Does a Chicken Take to Grow Before Slaughter

The time that takes to grow a chicken for slaughter depends on the breed and the weight that you want. Typically, chickens will be ready for slaughter and can be placed in the freezer in 6 to 12 weeks.

Broiler-fryers can be slaughtered at 7 weeks old. Roasters are considered older chickens as they’re good for slaughter in 3 to 5 months.

Baking or stewing hens are ready to be slaughtered in 10 months or a year and a half. The male chickens called capons are set for human consumption at the ages of 16 weeks to 18 months.

What Is the Lifespan of a Chicken?

What is the Lifespan of a Chicken

The lifespan of a chicken is 6 to 8 years.

How Do Chickens Grow So Fast?

How Do Chickens Grow So Fast

The usage of hormones to force the chickens’ maturity and make their bodies bigger is prohibited in the United States. Anyway, the expenses for this supplementation are higher than the chicken’s value in the present market. Here are the procedures made to grow chickens fast:

Genetic Selection

Genetic selection among chickens is similar to other animals like dogs. There are small breeds like Chihuahua and larger ones like Saint Bernard. Then, the largest Saint Bernard is picked to create the best one among the rest.

The same process is applied to obtain the greatest candidate. It’s not a problem for scientists since 8.6 broilers are produced in the United States every year.

It took 45 years to make the stocky broilers that are enjoyed by people today. Chickens with strong immunity against diseases, excellent growth rates, and effectiveness in feed conversion are the prospects for genetic selection.

The study of the process to make chickens grow fast was released in the Korean Journal for Food Science Animal Resource. To enhance poultry meat, fat content should be lowered.

The making of quality meat involves muscle fibers. A certain fiber type composition is based on species, genotype, sex, breed, feeding system, diet, age, muscle location, and growth performance.

Generally, wild birds have smaller muscle fibers than domesticated chickens. Furthermore, muscle mass is determined from the number of fibers before birth and the fiber size after birth.

Balance of nutrients and enough energy level can increase growth rate. Additionally, the main focus on this is to enlarge the breast. Still, all of these are important aspects to speed up the growth rate.

Improved Poultry Nutrition

In the last decades, it can’t be denied that there’s improved poultry nutrition. Experts have discovered the specific nutrients that boost the growth of broilers.

Their feed consists of corn (primary energy source), enzymes, vitamins, minerals, and soybean meal for protein.

At What Age Do Chickens Start Laying Eggs?

Chickens, specifically hens, can start laying eggs when they’re around 18 to 22 weeks.

Related: How Many Eggs Will a Chicken Lay? | All You Need to Know!

The Life of a Chicken

The Life of a Chicken

The life of a chicken starts with the union of an egg from a hen and sperm from the rooster. It takes 24 hours to complete fertilization. When the single cell is formed, it breaks into 2 parts. Then, it becomes 4, 8, 16, and the same pattern goes on.

Consequently, the right time will come for the hen to lay eggs that need to be incubated. In addition, the ideal temperature is crucial for the development of the chicks.

It takes 21 days for the chicks to be free from the shell. However, it will take 4 to 12 hours to completely release the chick from the egg.

The chick will come out wet but it dries in a few hours to uncover a fluffy appearance. It’s fully feathered but somehow very soft. Hence, it’s not capable of regulating its body temperature, so it should live with a source of heat.

But the feathers grow fast, and it only takes 8 weeks for the chick to be able to keep the normal body heat.

The chicken’s maturity is determined by its ability to reproduce. At 4 months, roosters start to mate, while it’s at around 6 months for the hens. The growth within the first 6 months can be slow, but the rate will be surprising after this period. Chickens can continue to grow bigger for up to 12 months.

Combs and wattles become bigger too. The spurs of the roosters will be noticeably larger. When the 12 months are over, you will see the maximum size of your chicken.

What Are the Factors That Can Affect Growth and Life Expectancy of a Chicken?

Temperature and Humidity Throughout the Growth Cycle

House temperature within the poultry should be consistent, especially in the early life of chickens. This will also benefit them in later life. Good control of humidity improves the welfare of these fowls. So, checking the temperature is usually done on the floor.

Management Practices and Equipment

These factors build the environmental condition. Apart from air control and ideal ventilation, poultry owners should also be attentive to the litter quality, numbers of stockmen, and type of drinker. A good drinker for chickens is RentACoop Automatic Chicken Nipple Water Cup Chicken Waterer.

The chickens should be comfortable to promote growth. Overcrowding doesn’t only cause disease but makes transmission fast. Cannibalism also happens when chickens peck among themselves. This is likely to happen if they compete for food and water. 

Feed Intake

You can easily know the right feed for chickens, like a protein diet and balanced formulated feed. However, it is sometimes altered by the environment so you have to learn how to adjust the daily feed intake.

In a study, chickens that are placed under an area with a high temperature (31.1°C) had a lesser feed intake compared to those who are under lower temperature (20°C). Therefore, the chicken in 20°C will grow faster.

Related: What to Feed Backyard Chickens? | Information and Facts

Frequently Asked Questions

How Many Times A Day Should I Feed My Chickens?

You can just fill the feeder with food as chickens don’t overeat. So, they will just feed themselves when they need to. However, it’s best to feed hens twice a day based on the study about chicken’s feeding regimen. Unfortunately, it increases their cumulative mortality.

What Foods Are Safe For Chickens?

Chickens can enjoy treats aside from their daily feed. Here are the foods that are safe for them.

  • Fruits: Blueberries, strawberries, watermelon
  • Vegetables: Chard, kale, lettuce, turnip greens, broccoli, pumpkin, squash, cucumber, beets
  • Herbs: Basil, cilantro, lavender, mint, oregano, parsley, thyme
  • Perennials: Coneflowers, daisies, daylilies, ferns, hostas, roses

Should Chicken Be Fed in the Coop?

Chickens shouldn’t be fed in the coop, as they don’t stay up at night to eat and drink. It will only create a big mess in the coop. This can encourage the growth of molds and even diseases.

What Does Chicken Starter Feed Look Like?

Chicken starter feed looks like crumbled pellets.

Can Hens Eat Chick Starter?

Hens can eat chick starters, but it doesn’t have enough nutrients, especially calcium, which they need in producing eggs.

How Old Do Chickens Have to Be to Eat Corn?

Chickens can eat corn when they’re over 4 weeks old.


Depending on the breed, a chicken can grow up to 12 months. A longer time may be needed by bigger breeds. The expected growth rate happens if you provide the appropriate diet and environment.

To come up with excellent chicken meat, genetic selection and improved poultry nutrition are crucial. Thus, chickens nowadays grow quicker and bigger than the fowls in the past.

List of Sources

Poultry Meat Quality in Relation to Muscle Growth and Muscle Fiber Characteristics

Effect of Environment on Nutrient Requirements of Domestic Animals

Life Cycle of a Laying Hen

Raising Chickens for Meat

Why the Rapid Growth Rate in Today’s Chickens?

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