In this guide13 sections
- Key Points
- How Much Do Breast Implants Weigh?
- Breast Implant Weight Chart: 200cc to 800cc
- Do Breast Implants Weigh More Than Natural Breasts?
- Will Breast Implants Make Me Heavier on the Scales?
- Can Heavy Breast Implants Cause Back Pain?
- Do Heavier Implants Cause Sagging or Bottoming Out?
- Are There Lightweight Breast Implants?
- Does Implant Shape or Profile Change the Weight?
- How We Choose Implant Size at Centre for Surgery
- Frequently Asked Questions
- References
- Talk to a Surgeon About Implant Size
Key Points
- A silicone gel breast implant weighs roughly 1 gram per cc, so a 300cc implant weighs about 300 g (10.6 oz) and a pair about 600 g. In one clinical series, conventional implants with an average volume of 347 ml weighed 347 g on average.[1]
- Saline implants weigh almost exactly the same per cc as silicone gel implants. The shell is included in these weights and makes little difference to the total.
- Even large implants add little on the scales: a pair of 400cc implants weighs about 800 g (1.8 lb). What matters more is how heavy the implant is compared with your own skin and breast tissue.
- Larger, heavier implants stretch the tissues more over time. A 2023 study of 1,017 women found that bigger implant volumes were linked with more implant rupture and asymmetry.[5]
- Lightweight implants, filled with gel that contains tiny hollow microspheres, can be up to about 30% lighter than a standard implant of the same volume.[2]
- Choosing implant size from tissue measurements, rather than from a target cup size, is associated with low reoperation rates: 3% overall in 1,664 cases in one long-term series.[3]
How much do breast implants weigh? It is a simple question with a simple answer: about a gram for every cc. But the reason people ask it is usually more practical. Will implants show up on the scales? Will they feel heavy? Can heavy implants cause back pain, sagging or bottoming out later on? This guide answers each of those questions, with a weight chart for every common size from 200cc to 800cc, and explains how implant weight fits into planning a breast augmentation.
If you are trying to work out what a particular volume will look like rather than what it weighs, our guide to how breast implant sizes relate to bra cup sizes covers that. For the costs involved, see our breast augmentation cost guide.
How Much Do Breast Implants Weigh?
Breast implants are sold by volume, measured in cubic centimetres (cc), which is the same as millilitres (ml). Their weight follows almost directly from that volume. A silicone gel implant weighs roughly 1 gram per cc, so:
- a 200cc implant weighs about 200 g (7 oz)
- a 350cc implant weighs about 350 g (12.3 oz)
- a 500cc implant weighs about 500 g (1.1 lb)
Remember that you will have two, so the total added weight is double the figure for one implant.
Why silicone implants weigh about 1 gram per cc
Water weighs 1 gram per millilitre, and the silicone gel used in modern implants is close to water in density. That is why the weight of an implant in grams is almost the same as its volume in cc. Real implants bear this out. A 2023 comparative study in Clinical Hemorheology and Microcirculation ↗[1] recorded both the volume and the weight of the implants used in 92 reconstructions with conventional silicone implants: the average implant held 347 ml and weighed 347 g.
The figures in this article are calculated on that basis, at 1 g per cc. Individual implants vary slightly with the gel, shell and design, so treat every number here as approximate.
Do saline implants weigh the same as silicone?
Very nearly. Saline implants are filled with sterile salt water, which weighs almost the same as plain water, so a saline implant also comes to roughly 1 g per cc. There is no meaningful weight saving in choosing saline. In the UK, saline implants are now rarely used for cosmetic surgery, as cohesive silicone gel looks and feels more natural. Our comparison of silicone vs saline breast implants explains the other differences.
Does the implant shell add weight?
The outer shell of a silicone implant is a thin layer of silicone elastomer. It does add a little weight, but the weights recorded in clinical studies are for the whole implant, shell and gel together, and they still come out at about 1 g per cc.[1] The shell is not something that changes the answer in practice.
Breast Implant Weight Chart: 200cc to 800cc
The table below shows the approximate weight of one implant and of a pair at common sizes. These are not manufacturer figures: they are calculated from volume at roughly 1 g per cc, with ounces and pounds converted from grams.
| Implant size | Approx. weight of one implant | Approx. weight of a pair |
|---|---|---|
| 200cc | 200 g (7.1 oz / 0.44 lb) | 400 g (14.1 oz / 0.88 lb) |
| 250cc | 250 g (8.8 oz / 0.55 lb) | 500 g (1.1 lb) |
| 300cc | 300 g (10.6 oz / 0.66 lb) | 600 g (1.3 lb) |
| 350cc | 350 g (12.3 oz / 0.77 lb) | 700 g (1.5 lb) |
| 400cc | 400 g (14.1 oz / 0.88 lb) | 800 g (1.8 lb) |
| 450cc | 450 g (15.9 oz / 0.99 lb) | 900 g (2.0 lb) |
| 500cc | 500 g (17.6 oz / 1.1 lb) | 1.0 kg (2.2 lb) |
| 550cc | 550 g (19.4 oz / 1.2 lb) | 1.1 kg (2.4 lb) |
| 600cc | 600 g (21.2 oz / 1.3 lb) | 1.2 kg (2.6 lb) |
| 650cc | 650 g (22.9 oz / 1.4 lb) | 1.3 kg (2.9 lb) |
| 700cc | 700 g (24.7 oz / 1.5 lb) | 1.4 kg (3.1 lb) |
| 750cc | 750 g (26.5 oz / 1.7 lb) | 1.5 kg (3.3 lb) |
| 800cc | 800 g (28.2 oz / 1.8 lb) | 1.6 kg (3.5 lb) |
How much do 500cc breast implants weigh?
One 500cc implant weighs about 500 g, or roughly 1.1 lb (just over 17 oz). A pair weighs about 1 kg (2.2 lb). For comparison, a 350cc implant weighs about 350 g (12.3 oz) and a 650cc implant about 650 g (1.4 lb).
How much do breast implants weigh in kg?
For most women having a first breast augmentation, the pair of implants together weighs somewhere between about 0.5 kg and 1 kg. Only implants above 500cc each take the total over a kilogram, and an 800cc pair comes to about 1.6 kg.
Do Breast Implants Weigh More Than Natural Breasts?
Not by much. Natural breast tissue is a mix of fat and glandular (milk-producing) tissue. Fat is slightly lighter than water, which is why it floats, so a mostly fatty breast weighs a little less per cc than an implant, while denser glandular tissue is closer to the weight of an implant. In practice, an implant weighs roughly the same as the same volume of breast tissue would.
What does differ is how the weight is carried. Your own breast tissue grew gradually and is supported by its own internal framework. An implant adds its whole weight on the day of surgery, sitting on the lower part of the breast and stretching the skin and tissues around it. The heavier the implant compared with what you already have, the more work those tissues have to do over the years.
It also helps to keep the numbers in proportion. Women who have breast reduction surgery for heavy breasts often carry far more weight than any cosmetic implant adds: in a long-term Swiss study of 114 women, an average of 1,266 g of breast tissue was removed.[8]
Will Breast Implants Make Me Heavier on the Scales?
Only by the weight of the implants themselves, which for most sizes is between half a kilogram and a kilogram. That is less than the normal day-to-day change in body weight caused by food, fluid and hormones, so most people barely notice it.
In the first week or two after surgery you may find you weigh more than expected. That is mainly fluid: the intravenous fluids given during the operation and the normal swelling of healing tissue. It settles over the following weeks as the swelling goes down. Our breast augmentation recovery guide covers what to expect week by week, and drop and fluff explains how implants settle into their final position.
Can Heavy Breast Implants Cause Back Pain?
For most women with implants that suit their frame, no. A few hundred grams on each side is well within what the back, neck and shoulders are used to supporting, and it is a fraction of what many women with naturally large breasts carry.
Weight on the chest does matter when it becomes large compared with the body. In a 2015 study of 410 breast reduction patients in the Annals of Plastic Surgery ↗[7], women who needed larger amounts of tissue removed reported back pain, shoulder grooves from bra straps, rashes under the breast and poor posture more often than those with smaller reductions. The same principle applies to very large implants, especially on a small or slim frame: the bigger the load, the more likely it is to cause aching or strap grooving, and the more support the breasts need.
If you already have back or neck problems, mention them at consultation so they can be taken into account when choosing a size. For a fuller discussion, read our article on whether breast implants can cause back pain. Women who exercise a lot may also find our guide to breast implants for athletes useful.
Do Heavier Implants Cause Sagging or Bottoming Out?
This is where implant weight matters most. Skin and breast tissue stretch under a constant load. Over the years, a heavy implant on thin tissue can lead to:
- Sagging (ptosis): the breast and implant drop lower on the chest, sometimes needing a breast lift later.
- Bottoming out: the implant slips below the fold under the breast, so the nipple appears to point upwards. Our guide to bottoming out of breast implants explains the causes and treatment.
- Tissue thinning: the soft tissue over the implant thins, so edges and rippling become easier to see or feel.
Implant weight is not the only factor. Skin quality, pregnancy, weight change, age and where the implant sits (under or over the muscle) all play a part. But it is one of the few factors you choose.
What the research says about implant size and complications
The clearest data come from studies that follow large numbers of women over time. In a 2023 retrospective study of 1,017 primary breast augmentations in Plastic and Reconstructive Surgery Global Open ↗[5], larger implant volumes, and larger implants relative to body mass index, were linked with higher rates of implant rupture and asymmetry. The authors could not find a single size above which risks suddenly rise, which is why size is best decided case by case.
Implants that are too big for the breast cause problems too. In a 2025 study of 212 women, implant oversizing was an independent risk factor, raising the odds about six-fold, for capsular contracture, the hardening of scar tissue around an implant.[6] Experienced breast surgeons have also described how high- and extra-high-profile implants can thin and stretch the tissues, sometimes in ways that are hard to correct later.[4]
Large implants: extra things to weigh up
Very large implants, often 500cc and above, can give a dramatic result, but they put more load on the tissues and are more likely to need further surgery in the long run. Our article on large breast implants: pros and cons of XL breast augmentation covers this in detail, and how to avoid boob greed deals with the urge to go bigger at the last minute.
Are There Lightweight Breast Implants?
Yes. Lightweight implants use a silicone gel mixed with tiny hollow microspheres, which lowers the weight of the filling without reducing the volume. A 2026 manufacturer-sponsored multicentre study in the Aesthetic Surgery Journal ↗[2] describes them as up to 30% lighter than standard implants and reported good safety and satisfaction in 101 women followed for three to five years.
The 2023 study mentioned above shows what that means in practice: lightweight implants averaging 452 ml weighed 317 g, while conventional implants averaging 347 ml weighed 347 g.[1] The authors noted a slightly higher revision rate in the lightweight group, which they said needs further study.
Lightweight implants are a relatively new option with less long-term evidence than standard silicone gel implants. Centre for Surgery uses Silimed implants for breast augmentation; if implant weight is a particular concern for you, your surgeon will explain how they address it with the implant range they use, mainly through careful choice of size and profile.
Does Implant Shape or Profile Change the Weight?
No. Weight depends on volume, not shape. A 350cc round implant and a 350cc teardrop (anatomical) implant weigh about the same. Shape and profile change how that weight is distributed: a higher-profile implant concentrates the same volume over a narrower base, so it projects further from the chest wall and places more load on a smaller area of tissue.
Our guides to round vs teardrop implants and breast implant profile and projection explain these choices.
How We Choose Implant Size at Centre for Surgery
The safest way to choose an implant is to start with your tissues and work out what they can carry, then choose the look you want within that range. This approach is sometimes called tissue-based planning. In Tebbetts and Adams’s High Five decision process, published in Plastic and Reconstructive Surgery ↗[3], implant choice was based on five simple measurements of the breast and skin. In 1,664 cases followed for up to seven years, the overall reoperation rate was 3%, and only 0.2% of women had their implants changed for a different size.
At your consultation, you meet the surgeon who will operate. All our breast surgeons specialise in breast surgery. They will:
- measure the width of your breast and chest, the distance from nipple to fold and how far the skin stretches
- assess how much breast tissue you have to cover an implant, which also guides whether it goes over or under the muscle
- talk through the look you would like and show you how different volumes would sit on your frame
- recommend a safe range of sizes, profiles and shapes, explaining what each means for weight and long-term support
Virtual consultations are available for a first discussion, but you will need a face-to-face consultation before surgery. Further consultations before surgery are free, and we recommend a two-week cooling-off period between your consultation and your operation, so there is time to think about size without pressure. The general guide to breast implant sizes is a useful place to start.
Real Centre for Surgery patient after breast augmentation with 470cc implants. At roughly 1 g per cc, each implant weighs about 470 g.
Real Centre for Surgery patient, side profile six weeks after breast augmentation with implants. The final shape settles over three to six months.
You can see more results in our breast augmentation before and after photos.
The implants we use
We use Silimed breast implants, which come with a 10-year warranty covering rupture and grade III–IV capsular contracture. Implants are inserted using a Keller funnel, and every implant is recorded on the breast implant registry. For how long implants usually stay in place, see how long breast implants last, and if you already have implants that feel too heavy, our guide on whether you can reduce your breast implant size explains the options.
Breast augmentation is a cosmetic procedure and is not usually available on the NHS. The NHS guide to breast enlargement ↗[9] is a useful independent overview. Finance is available, subject to status; see our finance options.
Frequently Asked Questions
How much is 450cc in pounds?
A 450cc breast implant weighs about 450 g, which is just under 1 lb (about 15.9 oz). A pair of 450cc implants weighs about 900 g, or roughly 2 lb.
How big is a 340cc implant?
A 340cc implant weighs about 340 g (12 oz), but how big it looks depends on your starting breast size, chest width and the implant’s profile. On a slim, narrow chest with little breast tissue it can look full; on a broader frame with more natural tissue the change will look more moderate. There is no fixed conversion from cc to cup size.
Is it normal to gain weight after breast augmentation?
Yes, a little. The implants add their own weight, usually under a kilogram for the pair, and in the first week or two you may also hold extra fluid from the operation and from swelling. Weight gained from fluid comes off over the following weeks. Gaining several kilograms that do not go after a month or so is unlikely to be due to the surgery, and is worth discussing with your GP.
Is there a weight limit for breast implants?
There is no single maximum implant size or weight that applies to everyone. The practical limit is set by your own tissues: how wide your chest is, how much the skin can stretch and how much tissue there is to cover and support the implant. Your surgeon will recommend a range that your tissues can carry safely, and may advise against sizes outside it.
How many cc’s are in a full D cup?
There is no reliable answer, as cup sizes vary between brands and depend on band size: a D cup on a 30 band holds far less than a D cup on a 38 band. Surgeons plan in cc and centimetres rather than cup sizes. Our guide to implant sizes and bra cup sizes explains why.
Do breast implants feel heavy?
Most women say their breasts feel tight and heavy for the first few weeks, mainly due to swelling and stretched tissues. Once that settles, implants of a suitable size usually feel like part of the body. Very large implants are more likely to feel heavy long term, especially without a supportive bra during exercise.
Will my implants get heavier over time?
No. An intact implant keeps the same weight for as long as it is in place. What can change is how your tissues carry it: skin stretches with age, pregnancy and weight change, which is why implant breasts can drop over the years even though the implant itself has not changed.
References
- Heine N, Brebant V, Seitz S, Eigenberger A, Prantl L, Tessmann V. Lightweight implants in breast reconstruction. Clin Hemorheol Microcirc. 2023;84(1):103-109. doi:10.3233/CH-239101 ↗
- Reichenberger M, Hedén P, Germann G. Mid- to long-term outcomes following primary augmentation with B-Lite lightweight breast implants: a prospective multicenter postmarketing clinical follow-up study. Aesthet Surg J. 2026;46(9):NP88-NP96. doi:10.1093/asj/sjag105 ↗
- Tebbetts JB, Adams WP. Five critical decisions in breast augmentation using five measurements in 5 minutes: the high five decision support process. Plast Reconstr Surg. 2006;118(7 Suppl):35S-45S. doi:10.1097/01.prs.0000191163.19379.63 ↗
- Tebbetts JB, Teitelbaum S. High- and extra-high-projection breast implants: potential consequences for patients. Plast Reconstr Surg. 2010;126(6):2150-2159. doi:10.1097/PRS.0b013e3181f44564 ↗
- Medor MC, Bouhadana G, Churchill IF, et al. How big is too big? Exploring the relationship between breast implant volume and postoperative complication rates in primary breast augmentations. Plast Reconstr Surg Glob Open. 2023;11(3):e4843. doi:10.1097/GOX.0000000000004843 ↗
- Li XY, Xiao SQ. Analysis of risk factors for capsular contracture after breast augmentation: a retrospective study. Front Surg. 2025;12:1596993. doi:10.3389/fsurg.2025.1596993 ↗
- Strong B, Hall-Findlay EJ. How does volume of resection relate to symptom relief for reduction mammaplasty patients? Ann Plast Surg. 2015;75(4):376-382. doi:10.1097/SAP.0000000000000190 ↗
- Brühlmann Y, Tschopp H. Breast reduction improves symptoms of macromastia and has a long-lasting effect. Ann Plast Surg. 1998;41(3):240-245. doi:10.1097/00000637-199809000-00003 ↗
- NHS. Breast enlargement (implants). nhs.uk ↗
Talk to a Surgeon About Implant Size
If you are thinking about breast implants and want to know what size and weight would suit your frame, you can book a consultation at our Baker Street clinic by calling 020 7993 4849 or using the form below. You will meet the surgeon who would carry out your operation.
