A knee pillow can make back sleeping more comfortable by gently raising your legs and changing how your lower back rests against the bed. The best knee pillow for back sleepers depends on the kind of support you prefer: a firm wedge, a curved foam bolster, or a softer pillow that can also fit between your knees. Below, we compare five options and explain what to consider before choosing one.
Quick Comparison
| Product | Design | Best suited for |
|---|---|---|
| Shinnwa Convertible Knee Wedge Pillow | Convertible wedge with dual-layer foam | People who want adjustable cushioning and support |
| Everlasting Comfort Under Knee Pillow | Memory foam half-moon bolster | Back sleepers who prefer a curved leg bolster |
| 5 STARS UNITED Knee Pillow | Compact memory foam half-moon bolster | People seeking a smaller, straightforward support pillow |
| MINUPWELL Knee Pillow | Full-length, washable down-alternative pillow | People who want support under the legs or between the knees |
| TranquilRelax Half-Moon Knee Pillow | Memory foam bolster with removable cover | Back sleepers looking for a compact foam option |
Our Picks: Best Knee Pillow For Back Sleepers reviews
Shinnwa Convertible Knee Wedge Pillow: Best for Adjustable Support
The Shinnwa is a wedge-style pillow with a convertible design. Its firm, high-density foam base provides structure, while a two-inch shredded-memory-foam layer adds a softer surface. The topper can be flipped and secured with a zipper, so you can change which side gets the cushioning.
For back sleeping, the wedge shape gives your knees and legs a broad support surface rather than the narrow contact area of a half-moon bolster. The listing describes two sizes: medium at 23.5 by 18.8 by 8 inches and small at 21.7 by 16.5 by 6.3 inches. Check those dimensions against your bed and preferred leg position before choosing.
The convertible setup is the main reason to consider this model. You can position the topper for a softer knee surface, use the wedge in another orientation, or unfold the topper flat. That flexibility may suit someone still figuring out what shape and firmness feel comfortable. The trade-off is that it is larger and more involved than a simple bolster. It also arrives vacuum-compressed and may take up to 48 hours to fully expand.
Pros:
- Combines a supportive foam base with a soft shredded-foam layer.
- Convertible design offers more than one setup.
- Available in two listed sizes.
- Removable cover is machine washable; a laundry bag is recommended.
Cons:
- The wedge takes up more bed space than a compact bolster.
- Needs time to expand after unpacking.
Verdict: Choose the Shinnwa if you want a broad, adjustable wedge and value the ability to change the pillow’s feel and position.
Everlasting Comfort Under Knee Pillow: Best for a Classic Bolster Shape
This pillow uses a half-moon bolster shape designed to sit beneath the knees or legs. Its memory foam is intended to contour around the body, while the curved profile provides a defined support area without the wide footprint of a wedge.
The cover is described as breathable air-layer fabric and is removable and machine washable. The pillow is also described as suitable for placement under the knees, legs, ankles, or lower back, giving it some flexibility beyond bedtime. Because the listing does not provide dimensions, compare the shape and fit with your needs if you have a specific bed setup or want to support a larger area of your legs.
Compared with the Shinnwa, this is a simpler, less adjustable design. That can be a plus if you want a dedicated bolster rather than a convertible pillow. It may be less suitable if you want a broad wedge or need a pillow that supports the full lower leg from knee to ankle.
Pros:
- Curved half-moon shape is made for placement under the knees or legs.
- Memory foam is designed to contour to your body.
- Removable, machine-washable cover.
- Can also be positioned under the ankles or lower back.
Cons:
- Dimensions are not provided in the supplied product details.
- Does not offer the convertible positions of the Shinnwa wedge.
Verdict: This is a straightforward option if you prefer a half-moon bolster and want a removable, washable cover.
5 STARS UNITED Knee Pillow: Best Compact Memory Foam Bolster
The 5 STARS UNITED pillow is a compact memory foam bolster measuring 20.4 by 7.8 by 4.8 inches. Its half-moon shape is intended to support the knees, legs, hips, or ankles while you lie on your back. The smaller profile may appeal if you do not want a large wedge taking up much of the bed.
The product details describe the cover as breathable, anti-pill, removable, and washable. They also state that the cover is OEKO-TEX STANDARD 100 certified. The listing describes the pillow as endorsed by the American Chiropractic Association; that is a product-specific listing claim, not a substitute for medical advice or a guarantee of pain relief.
This model is a more compact alternative to the Everlasting Comfort bolster, with dimensions clearly stated in the supplied details. Its modest height may be a better fit for someone seeking gentle elevation than for someone who wants a taller, more substantial lift. It can also be placed between the knees or under the ankles, though its narrow shape is not designed to cushion the whole lower leg.
Pros:
- Compact size and clearly listed dimensions.
- Memory foam provides a shaped support surface.
- Removable, washable cover described as OEKO-TEX certified.
- Can be used under the knees, between the knees, or under the ankles.
Cons:
- Its compact size may not support the full length of the lower legs.
- Offers less elevation than a taller wedge pillow.
Verdict: Consider this pillow if you want a compact bolster with a washable cover and do not need broad or high leg elevation.
MINUPWELL Knee Pillow: Best for Full-Leg and Multi-Position Use
Unlike the foam bolsters, the MINUPWELL is a soft, full-length pillow designed to support the lower leg from knee to ankle. The listing describes a cotton shell and 7D down-alternative fill, with baffle-box construction intended to help keep the filling distributed. A center seam is also designed to help the pillow stay in position when you switch sides.
You can place it under your legs while sleeping on your back or between your knees when sleeping on your side. The product details say the whole pillow is machine washable, which may be useful if you prefer to wash the complete pillow rather than remove a cover. It is a different feel from memory foam: expect a softer, more pillow-like surface rather than a firm, shaped wedge.
This design may suit people who change sleep positions or want support across more of the lower leg. On the other hand, shoppers who want a precise, firm elevation angle may prefer one of the foam options. The supplied details do not list dimensions, so check the product listing if you need to confirm its size before buying.
Pros:
- Designed to support the leg from knee to ankle.
- Can be used under the legs or between the knees.
- Whole pillow is described as machine washable.
- Cotton shell and baffle-box construction are intended for softness and even fill distribution.
Cons:
- Soft fill may not provide the firm, defined support of a foam wedge.
- Dimensions are not provided in the supplied product details.
Verdict: Pick the MINUPWELL if you want a washable, soft pillow that can work under your legs or between your knees in different sleep positions.
TranquilRelax Half-Moon Knee Pillow: Best for a Simple Foam Support
This TranquilRelax half-moon bolster is made with a high-density memory foam core and a removable cover. It measures 20.4 by 8 by 4.9 inches, making it close in overall footprint to the 5 STARS UNITED option. Its curved profile is meant to elevate the legs when you are lying down without the wider surface of a wedge.
The cover is described as washable, and the foam is described as OEKO-TEX certified. The listing also presents the pillow as suitable for several positions and uses, including under the knees, as lumbar support, or for travel. Those are possible uses rather than a promise that one pillow will work equally well for every body or situation.
Compared with the 5 STARS UNITED bolster, the TranquilRelax has a slightly wider and taller listed size, while both have a compact half-moon shape and removable covers. If you want a simple foam pillow, either may be worth considering; the listed dimensions and your preferred height can help break the tie. Neither offers the broad, adjustable setup of the Shinnwa wedge.
Pros:
- High-density memory foam core with a half-moon shape.
- Dimensions are clearly listed.
- Removable cover is described as washable.
- Compact enough to use for more than under-knee support, according to the listing.
Cons:
- Does not have an adjustable or convertible design.
- Provides a narrower support area than a full-length leg pillow.
Verdict: The TranquilRelax is a practical choice if you want a compact memory foam bolster with a washable cover and clearly stated dimensions.
How to Choose a Knee Pillow for Back Sleeping
Choose a shape that matches your preferred support
A wedge supports a broader area and can give your legs a more elevated position. A half-moon bolster is narrower and easier to place beneath the knees, while a full-length pillow can support more of the lower legs. Think about whether you want a defined lift, a compact cushion, or support extending toward your ankles.
Consider firmness and fill
Memory foam and high-density foam offer a more structured feel than down-alternative fill. A foam bolster may suit you if you want a consistent shape under your knees. A softer, filled pillow may feel more familiar and can be easier to reposition between your legs. Neither feel is right for everyone, so use the product’s materials and shape as a guide.
Check the dimensions and height
Height affects how much your knees and legs are raised, while length and width affect how much of your body the pillow can support. Compare the listed measurements with your bed and your body position. If dimensions are not provided in the product details, check the listing before ordering rather than assuming the pillow will fit your needs.
Look for useful care features
A removable, machine-washable cover makes it easier to keep a foam pillow fresh, while a fully washable pillow may appeal if you want to clean the whole item. Check the care instructions for the specific model. For the Shinnwa, the product details recommend using a laundry bag when washing the cover.
Think about how often you change positions
If you stay on your back, a dedicated wedge or bolster may be enough. If you move between back and side sleeping, a pillow that can also fit between your knees may be more useful. Consider whether the pillow’s shape will remain comfortable when you shift, rather than choosing based only on how it looks in one position.
Set realistic expectations for comfort
A knee pillow can change how your legs are supported, but comfort is personal and results vary. It is not a treatment for the cause of back, hip, or knee pain. If pain is persistent, severe, or getting worse, ask a qualified health professional for guidance.
Frequently Asked Questions
Should back sleepers put a pillow under their knees?
Some back sleepers find that placing a pillow under the knees feels more comfortable. The right position and height vary from person to person, so adjust the pillow until it feels supportive without creating strain.
Is a wedge or a half-moon pillow better for back sleepers?
A wedge offers a wider support surface and a more elevated shape. A half-moon pillow is more compact and focuses support beneath the knees or legs. Choose based on the amount of lift and coverage you prefer.
Can I use a knee pillow if I sometimes sleep on my side?
Some options in this guide are designed for use under the knees while back sleeping and between the knees while side sleeping. The MINUPWELL is specifically described for both positions. Check the shape and size to make sure it suits how you move during the night.
Will a knee pillow relieve back pain?
A knee pillow may make a sleeping position feel more comfortable for some people, but it cannot guarantee pain relief or treat an underlying condition. For ongoing or concerning pain, consult a health professional.
How do I keep a knee pillow clean?
Follow the care instructions for your model. Several options here have removable, washable covers, while the MINUPWELL is described as machine washable as a whole pillow. Do not assume the foam core can go in the washing machine unless the product instructions say so.
How high should a knee pillow be?
There is no single height that works for everyone. A lower bolster may offer gentle support, while a taller wedge creates more elevation. Use the product dimensions as a starting point and choose a position that feels comfortable to you.
Final Recommendation
The Shinnwa Convertible Knee Wedge Pillow is the strongest option for shoppers who want adjustable cushioning and a broad support surface. For a compact foam bolster, consider the 5 STARS UNITED or TranquilRelax models and compare their listed dimensions. If you prefer a soft pillow that supports more of the lower leg and can also be used between the knees, the MINUPWELL is the most flexible choice in this group. Select the shape and height that fit your sleep position, and treat any pain-relief claims as potential comfort benefits rather than guaranteed results.