Cal King Purple Flat Foundation
The box spring, reinvented — durable with effortless assembly
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Frequently asked questions
California king size bed frames typically range from 71” - 77” wide and 83” - 89” long.
In general, bed frames are 2” to 5" wider and longer than their corresponding mattress sizes. However, some lower profile styles, like platform bed frames, may be closer to the exact dimensions of the mattress.
We recommend purchasing a bed frame for your Purple Mattress right here at Purple. We offer a wide range of ergonomic bed frames, foundations, and adjustable bases engineered for sturdy, creak-free support. If you’d prefer to experience them in person — find our assortment of bed frames at the closest retailer near you.
Purple California king size bed frames are available at a range of prices. For example, the sturdy Metal Platform bed frame is priced at $499 for a California king size. Our stylish Upholstered Bed Frame is priced at $880.
Our adjustable bases range from $999 to $2,595 for a California king size and offer a wealth of customizable comfort features that take R&R to the next level.
While a king size mattress and split king size mattress are different in that a split king is made of two individual twin XL size mattresses placed side by side, the total mattress dimensions are the same at 76” wide by 80” long. This means that king size mattress owners and split king mattress owners can both use a king size bed frame.
However, split king owners may prefer to add additional customization to their sleep by using a split king adjustable base — like the Purple Adjustable Base or Premium Plus Smart Base. By using a split king base, each sleeper can control elevation, lumbar support + more on their side of the bed.
California king size mattresses are longer and narrower than king and split king size mattresses, coming in at 72” wide by 84” long — so these mattresses are not compatible with standard king size bed frames. California king mattress owners will need to get a bed frame specifically designed for California king mattress dimensions.
If you’re looking for a king size or California king bed frame, check out the sturdy Purple Metal Platform, the stylish Upholstered Bed Frame, or the fully adjustable Premium Plus Smart Base.
No, mattresses and bed frames are sold separately, though we recommend checking out our sale page, as we often offer a discount when purchasing both.
If you’re looking for a California king size mattress, check out our bestselling California king size mattresses: the RestorePlus® Mattress and the RestorePremier® Mattress — with responsive coils for enhanced pressure relief and temperature balance.
Our patented GelFlex Grid is the only mattress material that instantly relieves pressure for pain relief and proven deeper sleep. The Grid also sleeps cool, minimizes motion transfer, and adapts to every body type + sleep position.
All Purple mattresses include free shipping, easy returns, a 100 night mattress trial, and a 10 year warranty.
Only our Upholstered Bed Frame includes both a foundation and headboard. Headboard brackets (compatible with most headboards) can be purchased separately for the Premium Smart Base and Premium Plus Smart Base.
Purple bed frames ship free of charge — except for addresses in Hawaii and Alaska.
Purple bed frames are designed with convenient under bed storage in mind. The Metal Platform provides 9” of under bed clearance, the Upholstered Platform provides 8”, and the Adjustable Base, Premium Smart Base, and Premium Plus Smart Base each have adjustable-height legs that offer a maximum of 12” clearance.
Note that under bed storage units are not included.
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