How Much Do 400 Cc Breast Implants Weigh?

I'm 5'7, 116 pounds and currently have a 34 A/B cup. I read online that one way to find out how big I should go was the birdseed-in-a-nylon route. After doing cup to cc conversion it came out to around 400cc's. The problem is, wearing the birdseed around got my neck and shoulder's quite sore. I'm worried that it will be the same with implants. Has anyone else complained of back/neck pain after implants?

Doctor Answers 13

Neck and back pain uncommon

Now that you have tried on sizers and chosen a volume that you like, you can calculate the weight of the implants.  The density of water is 1 gm/cc, so a saline implant that is 400 cc will weigh approximately 400 gm.  Two 400 cc implants will weigh 800 gm.  The conversion from gm to lbs is 2.2 lbs/kg.  So the implants will weigh approximately 0.8 kg x 2.2 lbs/kg = 1.76 lbs.  However, the implants are typically under the muscle and held close to your center of gravity.  They will not weigh on your neck like the birdseed does in the sizers.  People typically do not complain of back or neck pain after breast augmentation.

San Antonio Plastic Surgeon
4.9 out of 5 stars 136 reviews

400cc Saline Breast Implants Weighs 400grams

It’s not unusual for prospective breast augmentation patients to worry about the weight of their new breast implants. They worry that breast enlargement may create some of the symptoms that are frequently associated with breast hypertrophy such as back and neck pain.
In this case a 400cc saline breast implant weighs 400 grams. There’s 454 grams in a pound so these implants weigh about .88 pounds. When silicone implants are used they weigh approximately 15% more than saline implants.
Implants in this size range are easily tolerated by most patients and aren’t associated with back or neck pain. This is especially true when implants are placed beneath the muscle. Under these circumstances, the muscle produces added support for the implant.
If you’re concerned about the weight of your breast implants, consultation with a board-certified plastic surgeon is appropriate. This surgeon should be able to discuss this issue and alleviate your concerns.

Richard J. Bruneteau, MD
Omaha Plastic Surgeon
4.9 out of 5 stars 194 reviews

Any weight increase can pull you downward.

Breast implants generally do not contribute significantly to weight increases. For example, a 400cc silicone breast implant weighs 424gm or 15 ounces (roughly two pounds for a pair). 

Perhaps you'll be happy with a smaller size, so the best way to know the right thing to do is to go in for a consultation with your Board Certified Plastic Surgeon.

Hope this helps.

Best of luck.

Brian K. Brzowski, MD, FACS
Ogden Plastic Surgeon
5.0 out of 5 stars 76 reviews

How Much do Breast Implants Weigh?

Dear Grand Canyon Girl,

Breast implants weigh about one gram per cc, so a 400 cc implant weighs about 400 grams, or 0.88 pounds. It is uncommon for breast implants to cause neck or back pain.

Warmest wishes,

Larry Fan, MD

Larry Fan, MD
San Francisco Plastic Surgeon
4.3 out of 5 stars 14 reviews

Breast Implant Weight

For a 400 cc implant, each implant weighs less than one pound, or 0.88 lb to be exact.

This should not result in any back or neck pain. What you are experiencing is the result of you trying to simulate the look using the birdseed-in-a-nylon method.

Thanks to Vectra 3D imaging, these “tricks” to get a sense of what your breast implants will look like are now outdated. They have been replaced with a much more accurate simulation.

I hope that answers your question on implant weight. It’s great that you’re doing this research. I always say that the best patients are informed patients.

You might also want to research your options for breast implants. Choosing the right implant is the number one concern among women considering breast augmentation. Did you know, there’s actually a way to select a implant shape, size, and profile that is perfect for you?

A term that I use with my patients for the perfect implant is the “Pony Implant”.

So what do I mean by “perfect”? Well, a Pony Implant has three qualities to it. First, the implant meets your beauty goals. For example, you want to your breasts to look fuller while still appearing natural.

Second, when you chose your Pony Implant, you walk out of your consultation 100% confident that you’ve chosen the right shape and size for you. In other words, you won’t be second guessing your decision, and you won’t be afraid of having gone too big or too small.

And third, after your procedure, you are thrilled with your results, and say, "I’m so happy. This is exactly what I wanted!"

That’s the Pony Implant. And the great news is that there is a simple process to go about finding yours.

This issue of selecting the right implant is so important when it comes to patient satisfaction or dissatisfaction that, again, I really encourage you to learn more about it.

Thank you for reading and best of luck on your journey!

William Rahal, MD
Beverly Hills Physician
5.0 out of 5 stars 46 reviews

Breast Implant Weight

Hi Grand Canyon Girl, Interesting question and valid concern. First, 400cc implants weight less than a pound on each breasts. This is a substantial size implant, but if it's place correctly under the muscle, it should not feel heavy. They are deeper inside your body closer to your center of gravity so they won't feel the same as the testing sizers in your bra. I rarely see breast augmentation patients complain of back or neck pain unless they have a much older augmentation done over the muscle with very, very large saline implants.Most patients with these issues have naturally very large breasts, larger than any implant could make them. I might recommend doing your testing with sizers again, only using the Rice Test and see if you get a similar result. Good luck!

William Aiello, MD
Orange County Plastic Surgeon
4.9 out of 5 stars 51 reviews

It's about 1 gram per cc

A 454cc implant weighs about a pound. (454 gms equals 1 pound).

Certainly, overly large implants can lead to upper back/neck discomfort, but not typically in the 400cc range. When implants are much larger (500-600cc+) it is more common.

David J. Levens, MD
Coral Springs Plastic Surgeon
5.0 out of 5 stars 76 reviews

400cc Silicone Breast Augmentation

Watch this video of a 400cc Silicone Breast Augmentation.  I explain the surgery and let you see the actual implants used for the surgery.  The video will help explain the augmentation possible with a 400cc smooth round silicone breast implant.  I hope this helps!

Johnny Franco, MD, FACS
Austin Plastic Surgeon
4.9 out of 5 stars 123 reviews


As an approximation 1 cc equals one gram, so 400 cc's equals 400 grams. 
In pounds this would be about  0.88 pounds per implant

Larry S. Nichter, MD, MS, FACS
Orange County Plastic Surgeon
4.9 out of 5 stars 157 reviews

Calculating The Weight Of Breast Implants

The weight of breast implants varies slightly based on whether they are saline or silicone. For saline implants, or water weight, 400cc roughly equals 400 grams or just under a pound. (specifically it is 1.7 lbs for both 400cc salinje breast implants) Silicone implants will weight slightly more than saline but only by about 15%. (1.9 lbs for both 400cc silicone implants) For implants of this size, I have never seen or heard of a patient complaining of symptoms that are more typical of large breast reduction patient discomfort. This is because in breasts that sag or hang, they pull on the neck and back just like a rope around your neck with small weighted sacs attached to them. In the breast augmentation patient, the implants and breasts are up on the chest wall and not suspended or hanging. Pain, shoulder and neck pain from breasts is as much as their position on the chest wall as it is their size and weight.

Barry L. Eppley, MD, DMD
Indianapolis Plastic Surgeon
4.7 out of 5 stars 72 reviews

These answers are for educational purposes and should not be relied upon as a substitute for medical advice you may receive from your physician. If you have a medical emergency, please call 911. These answers do not constitute or initiate a patient/doctor relationship.