After learning how to compare springs and upholstery layers in mattresses, it’s hard to imagine comparing mattress foundations could be as complicated. After all, you don’t lay directly on the foundation, so how much of a role can it play? Well, believe it or not, the right foundation can add to your mattress’ lifespan and make your perfect mattress that much more comfortable. So when you’re shopping for a new bed, compare mattress foundations and pick one that helps you get the best support and the longest life out of your mattress.

Since the 1920s, box springs have been the go-to foundation for mattresses, but wood frames, steel and wood grids, and platform frames are some other mattress foundations you’ll see. Confused about which mattress foundation is best for you? Here are the pros and cons of each so you can compare mattress foundations and pick the right one for your needs.

Box springs

If you’re in the market to compare mattress foundations, there’s a lot to love about the box spring. They’re shaped like a mattress with wooden frames containing highly rigid metal coils. Some box springs also have a layer of firm foam for extra support. The outside of the frame is covered in fabric. Most manufacturers offer matching mattress and box spring sets where the fabric on both pieces is the same. While it’s not vital to have matching fabric, it’s a good idea to make sure your box spring matches your mattress for size. In other words, don’t use a full-size box spring to support a queen-sized bed. Uneven support can cause the mattress to wear out faster.

Box springs absorb 70% of the initial energy that hits it whenever you first get in bed (or move while you sleep), making them great at keeping the mattress as steady as possible. And because the mattress isn’t taking the full brunt of the movement, box springs also help extend the life of a mattress, especially if you have a basic metal bed frame.

Wood platform foundation

A less expensive option is the Ortho box or zero-deflection foundation. This is a very traditional mattress support constructed with several slats of wood covered by lightweight, compressed wood fiber material (to keep the mattress from sagging between the slats) and topped with fabric. The wood foundation adds extra firm support to your mattress, and because it doesn’t have metal coils, it’s usually lighter weight than most box springs.

Some platform-style beds do not utilize box springs either and are another option. They’re similar to a wood frame foundation, yet have a completely solid base. Platform beds are rising in popularity for loads of reasons. They’re great for smaller bedrooms; the extra space underneath where the box spring would be is a perfect spot for storage, or alternatively, the open air left under the bed can make the room seem much bigger.

Torsion grid foundation

Torsion grids are typically an expensive foundation style and rare than a standard wood platform or box spring. The inside of a torsion grid foundation looks like a honeycomb. It can be made with wood or steel. Some units use interlocking pieces of wood or steel to form a grid, while some use square-shaped rigid metal coils attached to a wood frame.

The torsion grid provides even, firm support across the mattress surface, and it helps extend the life of the mattress, similar to a box spring. However, these are likely to be paired with the highest-priced mattresses, so consider your budget.

One note about foundations: standard foundations are 9″ high, but since mattresses have become thicker in the last several years, you can also find lower profile bases. A 5″ box spring has the same ability to transfer energy as its 9″ counterpart, and if you have a higher bed, it might save you from needing a stepladder to get in at night.

Specialty foundations

For some, a flat, rigid mattress foundation isn’t the right choice. Adjustable beds can help with health conditions and sleep problems, and these require adjustable foundations as well. Specialty foundations like the Simmons Beautyrest Black Luxury Adjustable Base let you raise or lower portions of your mattress to improve breathing, relieve pressure, or just watch TV comfortably in your bedroom. The base offers the same life-extending mattress support but also allows you to customize your bed position.

The beds shouldn’t be complicated, just comfortable. When you’re shopping for a mattress foundation, think about the ideal lifespan for your mattress, the style of bed you have, and how firm you like your sleep surface. Everyone has their own preference. It’s up to you to have your Goldilocks moment and find which foundation works best for you and your body.