Purple Flex Review

In This Review
Performance Tests | Firmness | Support & Sleeping Positions | Design | Materials | Comparisons | FAQs

At NapLab, we put each mattress to the test.

We test 10 different factors that impact the performance, comfort, and value of the mattress. Testing categories include:

Test	Rating
Cooling	Very Good
Sinkage	Very Minimal
Motion Transfer	High
Response Time	Extremely Fast
Bounce	High
Edge Support	Very Good
Sex	Excellent
Pressure Relief	Fair
Off-Gassing	Excellent
Company	Excellent

Cooling performance on the Purple Flex is good, but far from great. In our cooling tests, I felt a slight to moderate level of heat retention around my body.

The Flex has a fairly basic material design, including the 2.0” gel pad (Purple’s hyper-elastic gel polymer grid) and a 6.0” support foam. While the gel layer doesn’t retain heat and has good airflow (due to the grid design) it sits on a less breathable support poly foam.

• Baseline Temperature – the temperature of the mattress before anyone lies on it
• Maximum Temperature (0 minute) – the temperature of the mattress after lying on it for 15 minutes
• Ending Temperature (5 minute) – the temperature of the mattress after being lied upon and having no one on it for 5 minutes

Having only 2.0” of material between sleepers and the support foam just isn’t ideal. That support foam is able to come into more contact with body heat, retain it, and gradually warm the mattress.

Higher performance Purple mattresses have a thicker gel grid comfort layer and/or use pocketed coils instead of support foam, both of which have a significant impact on their cooling performance.

Without these material enhancements, the Purple Flex struggles more to keep the mattress cool.

In our objective cooling tests, we measured a max surface level temperature of 90.7°.

Heat Dissipation Over Time

From minutes 0 to 1 the temperature declined by 3.1°. From minutes 0 to 5 the decline was 4.9°. Both of these are notably worse than the average minute-by-minute decline.

The Purple Flex has a very minimal level of sinkage. In our pressure point sinkage tests, we measured a total sinkage depth of 1.66”. This is 0.54” less sinkage than the average of 2.20”.

The level of sinkage is documented in the image below.

The Flex creates more of a “floating on top of the mattress” feel, as opposed to lying “in” the mattress. Heavier parts of my body (namely butt and mid-section) sink more deeply.

However, most of the body (arms, head, legs, etc.) float on top. For the portions that do sink down the mattress has a more generalized and rounded contouring hug around the body.

The more generalized body contouring doesn’t conform as precisely to the body compared to the way memory foam and even many types of poly foam will. This isn’t a pro or con, but it is a specific feel that some sleepers greatly enjoy, but many will prefer a more precise contour. 

The Purple Flex mattress has a high level of motion transfer. In our tests, we measured a total acceleration range of 12.72 m/s². This is 4.85 m/s² more motion transfer than the average of 7.87 m/s².

The level of motion transfer is documented in the video below.

When it comes to motion the Purple Flex has a lot going against it. The medium-firm feel, 8” thickness, thin 2” comfort layer, and thin cover are all working against it.

With only 2.0” of gel comfort material on top there just isn’t much material in the way before sleepers hit the more dense and hard support foam. The support foam returns energy more abruptly and doesn’t isolate in the same way that a pocketed coil unit will.

Looking at our motion transfer chart, which visualizes our accelerometer data, we can see high levels of motion from 0 to 0.64 seconds. While motion begins to drop after 0.64 seconds it remains moderately high until 1.34 seconds.

Both the motion duration and motion peaks speak the same story. The Purple Flex has a high level of motion transfer.

The Purple Flex has an extremely fast material response time. In our tests, we measured 0.2 seconds for the materials to mostly recover and 0.3 seconds for a full material recovery.

This is tied with the fastest mattress responsiveness we’ve tested to date. It is effectively an instant recovery speed and on par with other Purple mattresses, natural latex, coil units, and other highly responsive poly foams.

The level of responsiveness is documented in the video below.

The instant response speed prevents any type of a stuck feeling and helps sleepers more easily move around on the mattress.

The Purple Flex has a high level of bounce. In our tests, we measured a total bounce height of 11.29”. This is 1.66” more bounce than the average of 9.63”.

The combination of a thin total mattress height of 8.0”, thin cover, 2.0” of gel, and dense 6.0” support base all work together to create the higher bounce.

When people or objects come into abrupt contact with the mattress it quickly absorbs and returns the energy, creating a higher level of bounce.

The level of bounce is also documented in the video below.

Mattresses with a quilted cover, softer materials, and/or a thicker comfort layer typically serve to reduce bounce (and also motion transfer). Purple’s Flex has none of these materials or design elements.

As such, it comes as no surprise that we measured a higher bounce rate. The higher bounce serves to improve sex and enhance ease of movement, though it also has a negative impact on motion transfer.

Edge support on the Purple Flex leaves much to be desired.

In our sitting edge support tests, we measured a total sitting sinkage of 4.50”. This is 0.19” more sinkage than the average of 4.31”. That said, being near average isn’t great.

In general, I like to see 4.0” of sitting sinkage or less, with less always being better. Purple’s Flex is far from that mark.

The level of edge support while seated is documented in the images below.

Lying edge support was yet more unimpressive. While lying on the edge of the mattress I did not feel well supported in any position. In my view, this has less to do with the support of the edge specifically, and rather a lack of support on the mattress at large (which we discuss in-depth a few sections down).

The level of edge support while lying is documented in the images below.

This is only an 8.0” mattress with just 2.0” of comfort material. This is wholly insufficient for adult body weights, in my view.

Overall, I am just not happy with the level of edge support we experienced on the Purple Flex. It is outclassed by every other Purple mattress (and numerous other brands) we’ve tested.

The best mattresses for sex have high bounce, good edge support, quiet materials, and good pressure relief and cooling.

These 5 factors make up the NapLab sex performance score.

Sex Factor	Factor Weight	Score	Rating
Bounce	60%	10	High
Edge Support	20%	9.3	Excellent
Noise	10%	10	Minimal
Pressure Relief	5%	8.0	Okay
Cooling	5%	9.0	Excellent

For the Purple Flex, these individual factors generated a sex score of 9.7.

The Purple Flex has a high level of bounce which really carries the score for this mattress, considering bounce is worth 60% of the score. Edge support is good enough to not drag the score down, although not great.

This mattress is bouncy and supportive, with mild heat retention and okay pressure relief. There is only 2″ of comfort materials which may cause pressure relief issues for some people, but not all.

Pressure relief on the Purple Flex mattress is fair and leaves much to be desired. During our tests, I experienced a moderate level of pressure point build-up.

In my view, this is the cause of the mattress design itself. The Flex only uses 2.0” of comfort material on top of a standard 6.0” support foam base. This thin comfort layer causes sleepers to sink through it and more abruptly into the support foam.

The support foam creates more intense pushback, which creates the pressure point issues. During my tests, I felt a notable level of building pressure in my lower back and shoulders.

Speaking from experience personally testing 320+ mattresses, this is less an issue with Purple’s Flex specifically, and more a problem with almost all 8.0” mattresses.

In my view, 8.0” just isn’t enough material thickness to create proper pressure relief for adult weighted sleepers.

Off-gassing on the Flex mattress is strong right out of the box. It smelled for 4 days before the odor dissipated.

This duration is slightly longer than the 3-day average across all mattresses tested to date, but still not bad.

The company score takes a look at factors that may influence your experience with the mattress.

Factors include length of the trial period, warranty, shipping / return costs, and country of origin.

Company Factor	Factor Weight	Score	Data
Trial Period	25%	9.0	100 nights
Warranty	25%	10	10 years
Shipping	25%	10	$0
Returns	25%	10	$0
Country of Origin	0%		USA

For the Purple Flex, these individual terms and conditions generated a company score of 9.8.

It comes with a 100-night trial period and a 10-year warranty. For reference, the average mattress trial period is 160 nights, so the Purple trial is less than average.

That being said, the 100-night trial gives you over 3 months to decide if the mattress works for you, which should be suitable for most sleepers.

Shipping and returns are both free if the mattress ends up not working out.

Firmness on the Purple Flex 6.5 out of 10, creating a medium-firm feel.

This firmness would typically be suitable for a wide range of sleepers. But on the Flex, firmness and support are both contributing factors to the limited target audience that may be right for this mattress (more on that below).

Support on the Purple Flex is fair at best. During our tests, I experienced significant support issues. First and foremost, the mattress is only 8.0”. There are very few mattress types that are able to create proper and full support for adult body weights with only 8.0” of materials.

Sleeper Weight	Stomach Sleepers	Side Sleepers	Back Sleepers
Under 150 lbs.	Yes	Maybe	Yes
150-250 lbs.	No	No	No
250-300 lbs.	No	No	No

Typically, I want to see at least 10” of mattress thickness, with 12-14” being far preferable. At only 8.0” thick we just don’t have enough material support to create full support.

I am a fairly lightweight man at 140 pounds and I easily bottomed out the mattress when moving forward or getting in / out of bed. That simply should never happen.

The thinner profile means sleepers sink through the top 2.0” of comfort material and into the support foams. This abrupt contact with the support layer (due to a lack of transitional material and/or thicker comfort layer) will create pressure points for many moderate and heavier-weight bodies, in addition to most side sleepers.

Overall, the support dynamic on the Purple Flex just leaves much to be desired. I could see lighter-weight sleepers (especially back and stomach) finding it acceptable.

In addition, it would be a fine choice for many children. However, an 8.0” mattress with only 2.0” of comfort material just isn’t a mattress I feel confident recommending to adult sleepers.

Design

The Purple Flex mattress was introduced into the Purple lineup as a budget-friendly introduction to the Purple grid material. It has 2 layers of material compared to 3 layers on the Purple Original mattress.

The Purple Flex mattress is only 8″ thick, which poses some issues in terms of performance. For comparison, the average foam mattress is 10.52″ (based on all of our foam mattress tests to date). Although Purple is not a 100% foam mattress, I would expect the thicknesses to be similar and the Flex falls 2.52″ thinner than this benchmark.

Materials

There are two primary stacked layers on the Purple Flex mattress, as listed below, from top to bottom.

• 2.0” gel pad
• 6.0” support foam

In addition to these two layers, there is a perimeter edge support foam that is designed to improve edge support, although improvements aren’t drastic in this area, as we saw in the edge support tests above.

The thickness of the perimeter edge foam is noted below:

• 4.0” wide layer at the edges of the mattress
• 10.0” wide layer at the head / foot of the mattress

The Cover

This mattress has a stretch knit cover with a geometric stitching pattern and a smooth, clean feel.

The Comfort Layer

The comfort layer is the 2.0″ Purple grid material. This layer sits directly below the cover and is wrapped in the perimeter foam for additional edge support.

While we have been repeatedly impressed by the performance of the Purple Grid in other Purple mattresses (ex. Purple Hybrid, Purple Hybrid Premier 3 & 4), the performance of the grid on the Flex falls flat.

The Original Purple and Purple Hybrid mattress both only have 2″ of Purple Grid material and had better support and overall comfort than the Flex.

The Support Layer

Beneath the grid is a 6.0″ support foam base which did not feel supportive enough in our performance tests. The average thickness of the support layer across all foam mattresses we’ve tested to date is 6.6″ and the mattresses with thinner support layers tend to have thicker comfort layers and layers of transitional material as well.

On the Purple Flex, we don’t see any transitional material so the thinner layers can be a bit problematic here.

I consider myself to be a lightweight sleeper at only 140 lbs., but even at my weight, I can easily bottom out the mattress when sitting and getting on / off the mattress. Heavier sleepers would be expected to struggle even more.

Product Evolution

The Purple Flex was released in October 2022. It was launched as a budget-friendly alternative to the Purple Original mattress, offering a slightly firmer feel and thinner comfort layer.

Since launch there have been no changes to the design, materials, or price.

How is the Purple Flex Different?

Overall, the differences on the Purple Flex are not really putting this mattress in a positive light.

Granted, the biggest difference that you’re getting is the Purple Grid material, which is unique to Purple mattresses.

Compared to the average foam mattresses, the Purple Flex mattress is a worse performer than average, while also being at a higher price point by nearly 20%.

The Purple Grid gives the Flex less sinkage, higher motion transfer, and higher levels of bounce than average.

Edge support while lying is significantly below average and it’s got a thinner comfort layer by over 50%.

Factor	Purple Flex	Average
Overall	9.05	9.51
Price	$1299	$913 (foam mattresses)
Cooling Score	9.0	9.44
Max Sinkage	1.66″	2.20″
Total Motion Transfer	12.72 m/s²	7.82 m/s²
Response Time	0.2 sec.	0.4 sec.
Total Bounce	11.29″	9.62″
Edge Support – Sitting Sinkage	4.50″	4.32″
Edge Support – Lying Support	Fair	Excellent
Sex Overall	9.7	9.6
Comfort Material	2.0″	4.14″
Off-Gassing – Smell	Strong	Strong
Off-Gassing – Days	4 days	3.84 days
Trial	100 days	160 days
Warranty	10 years	28% have lifetime warranties, average of other 72% of mattresses is 13 years

Purple Original vs. Purple Flex

Other Mattresses to Consider

While the Purple Flex may be suitable for children and very light weight adult sleepers, there are few adult sleepers to who I would recommend this mattress. If you’re looking for a high-quality foam mattress, I would recommend one of the three alternatives below.

Frequently Asked Questions

Still have questions? Check out some of the top FAQs on the Purple Flex mattress below and get the answers you’re looking for.