400cc vs 425cc Breast Implant Sizers

Drag the slider to compare the same model without sizers and wearing 400cc Oumènta breast implant sizers.

External sizing demonstration only. Not a prediction of surgical results.

Choose your Pocket Bra by your current band size:

Because this kit includes a size above 400cc, we recommend Small (S) rather than Extra Small (XS) if your band is 32" or smaller.

The Pocket Bra should feel snug and supportive, similar to a sports bra. A steady fit keeps both sizes in the same position, which matters when only 25cc separates them.

Leaning a Little Smaller? Compare our 375cc vs. 400cc 2-Pack or our 350cc vs. 400cc 2-Pack.

Leaning a Little Larger? Compare our 425cc vs. 450cc 2-Pack or our 425cc vs. 475cc 2-Pack.

Want a More Noticeable Difference? Our 400cc vs. 450cc 2-Pack and 375cc vs. 425cc 2-Pack each compare two sizes 50cc apart.

Want a Third Size? Explore our 350cc vs. 400cc vs. 450cc 3-Pack or our 400cc vs. 450cc vs. 500cc 3-Pack, or build a custom kit with 400cc, 425cc, and 450cc. You can also choose any two volumes with our Choose-Any-2 Sizer Kit.

400cc vs. 425cc Breast Implants: How Different Are They?

425cc has 25cc more volume per breast than 400cc. That's about 6% more sizer volume, or roughly 1.7 tablespoons per side.

That doesn't mean your breasts will look 6% larger. The percentage describes the volume of the sizer, not your overall breast size. How either volume looks on you depends on your existing breast tissue, chest width, and frame, and after surgery also on implant profile and placement.

Five Steps to a Fair Comparison

1. Seat the sizers the same way every time. Make sure each sizer sits fully and evenly in its pocket before you look in the mirror. A sizer that has shifted can make one size look smaller or less even than it is.

2. Set your straps once. Adjust the Pocket Bra straps to a comfortable, supportive fit, then leave them. Changing them between sizes changes how the sizers sit.

3. Check symmetry. Face a mirror and confirm both sides look even before judging a size. Small adjustments can make a noticeable difference.

4. Compare within the same few days. Many women notice their breasts can feel or look fuller at different points in their monthly cycle. Trying both sizes within the same short window keeps your comparison consistent.

5. Keep everything else the same. Same outfit, same mirror, same lighting, same time of day. Then the only thing changing is the size.

Is 425cc Worth It Over 400cc?

That depends entirely on what you see and feel. Some women find that 425cc gives them a little extra fullness they really like. Others decide 400cc already does everything they wanted. A careful comparison helps you judge whether the extra 25cc matters to you.

If neither feels quite right, try 450cc for more fullness, or 375cc for a little less. For a wider look at this range, read 350cc vs. 450cc Breast Implants: Which Size Is Right?

Bring your photos and notes to your consultation. A careful comparison gives your surgeon a reliable picture of what you prefer.

Will 400cc or 425cc Give Me a D or DD Cup?

There's no reliable conversion between implant volume and cup size. The same volume can look different on two women, and cup sizes vary between bra brands. Oumènta sizers show you external volume under clothing; they can't predict your cup size after surgery.

For more on volume and cup size, read A Cup to C Cup Breast Implants: How Many CCs?

Why Try Sizes Before Surgery?

In a published study of 567 women, a group who tried silicone implant samples in a bra before surgery generally reported that the preoperative sizing process was helpful. The study used implant samples, not Oumènta sizers, and doesn't show that Oumènta products affect surgical outcomes.

Read the published preoperative sizing study.

Explore Individual Breast Implant Sizer Sizes

Learn more about our 400cc breast implant sizers, 425cc breast implant sizers, and 450cc breast implant sizers, or try our Breast Implant Size Calculator for a suggested range of sizes to try.

For more about choosing a size, read What Is At-Home Breast Implant Sizing?, What's the Average Breast Implant Size?, and How to Choose the Right Breast Implant Size, or browse our full Breast Implant Sizing Guide.

How much bigger is 425cc than 400cc?

425cc has 25cc more volume per breast, about 6% more than 400cc. The visible difference is usually subtle and most noticeable in fitted clothing and from the side.

Which Pocket Bra should I choose if my band is 32" or smaller?

Choose Small (S). Because this kit includes a size above 400cc, we recommend Small rather than Extra Small for bands of 32" or smaller.

Why do my sizers look different from one day to the next?

Small changes in how the sizers sit, how the bra straps are adjusted, or where you are in your monthly cycle can affect how a size looks. Keeping your setup consistent makes your comparison more reliable.

Should I get 400cc or 425cc breast implants?

That's a decision for you and your plastic surgeon. Wearing both sizes at home can help you understand which look you prefer. Your surgeon will assess your anatomy and recommend implant dimensions that suit you.

Why buy a 2-Pack instead of a 3-Pack?

If you've already narrowed your choice to 400cc or 425cc, a 2-Pack focuses on just those two sizes, at a lower price. If you're still exploring, a 3-Pack or custom kit adds a third size for a wider comparison.

Will these sizers show me how my implants will look?

No. Oumènta sizers show external volume under clothing. They can't reproduce implant placement, tissue response, implant profile, or surgical results.