Sleeping Pad R-Value Explained, and Which Pad Fits Each Season

If you've ever woken up at 3 a.m. with a cold hip inside a warm sleeping bag, the ground was the problem. As REI's sleeping pad guide puts it, you lose body heat to the cold ground beneath you, and what slows that loss is the pad. The number that describes how well a pad does that is its R-value, and it's the most useful spec on a sleeping pad that most people skip.

This article explains what R-value measures, how the industry test works, and what range each season calls for. It then shows where OGERY's pads fit, including which one puts an R-value in its product name and how to read the rest. We haven't slept on these pads ourselves. Product figures are OGERY's published specs, and the general facts come from the standards body and the outdoor-industry sources named below.

What R-value actually measures

R-value is thermal resistance: how strongly a material resists heat flowing through it. For a sleeping pad, that means how well it stops your body heat from passing down into the ground. Higher numbers insulate better. Per REI, a pad rated 2.0 is twice as warm as one rated 1.0.

That scale matters because the ground is almost always colder than you are. REI notes that any surface cooler than 98°F will draw heat from your body. On a cool night, that is almost every campsite.

Two things R-value is not:

• It isn't a temperature rating. A pad doesn't come with a "good to 20°F" label the way a sleeping bag might. The R-value is a physical measurement, and you match it to conditions using the season guide below.
• It isn't thickness. Thickness alone doesn't set it. Therm-a-Rest's engineers, interviewed by SectionHiker, named the three variables that change their pads' R-values: the number of internal chambers, radiant (reflective) layers, and foam thickness.

How the ASTM F3340 test works

Until recently, brands measured R-value in different ways, so their numbers couldn't be compared. That changed with ASTM F3340, the "Standard Test Method for Thermal Resistance of Camping Mattresses Using a Guarded Hot Plate Apparatus." Per SectionHiker, it reached shoppers in 2020, and major pad brands now rate to it.

How it works, according to the ASTM scope and the SectionHiker interview:

• The pad is held under a constant compressive force between a heated plate and a cold plate, and the heat flowing through it is measured.
• Readings are taken at three spots on the pad, and three identical pads are tested and averaged.
• It applies to every pad type: air pads with or without insulation, air pads with reflective materials, self-inflating foam pads, and closed-cell foam mats.
• Anything removable, such as a sleeping bag or mattress cover, is excluded from the measurement.

ASTM also states the limit plainly: the result is a repeatable comparative number, and it may not always match real-world performance, because real sleep adds edge heat loss, uncovered areas, changes in compression and shifting posture. Use it to compare pads, not as a guarantee for a particular night.

What this means when you shop: an R-value is most useful when you know it was measured to ASTM F3340. If a product page gives a number but no test method, it may not be directly comparable with ratings from brands that use the standard.

Which R-value for which season

REI's guide gives these ranges, pairing each one with an expected overnight low and a bag rating:

Swipe sideways to see the whole table →

One more fact from REI changes how you read sleeping bag labels: sleeping bag temperature ratings assume a pad with an R-value of 4. If your pad is well below that, your bag won't perform to its rating. Warm sleepers may manage with R 2–3 in most seasons, and cold sleepers should go higher.

Season by season

Summer and mild nights

With lows around 50°F or higher, comfort matters more than insulation. REI's own specialist says summer pads are fine for most three-season use, and that winter is when ratings really matter. This is where a thick air pad earns its place.

The Ultralight 6" Inflating Pad is OGERY's thickest air pad: about 6" inflated, with a single size listed at about 79" × 27.5". It has a built-in pillow, an integrated foot pump, dual-layer valves and a 50D polyester shell with a TPU coating. OGERY lists it at about 2.4 lb, packing to about 5.9" × 5.9" × 11". Side snaps join two singles into a double. Its product name and feature bullets don't give an R-value, and the figures in OGERY's comparison chart on Amazon don't name a test method, so treat it as a comfort pad for mild conditions rather than a cold-weather one.

Spring and fall

Shoulder seasons are where people get caught out. REI makes a point that's easy to miss: spring camping calls for a warmer pad than fall, because the ground hasn't warmed up yet after winter. Nights near freezing put you in the R 2–3.9 band, and if you run cold, the R-4 assumption behind your bag rating matters too.

For car camping, OGERY's memory-foam pads trade air bounce for foam feel. The 3" Memory Foam Self-Inflating Pad is about 3" thick and self-inflating, aimed at tents and car camping. The 3.15" Foam Pad + Electric Pump adds an electric pump. Neither puts an R-value in its product name or feature bullets, and any figure elsewhere on their Amazon pages comes without a test method, so on a cold spring night you can't tell from the specs how they compare with a rated pad. If you expect frost, choose a pad with a stated number. The foam pads are a car-camping comfort choice: REI notes that foam-based self-inflating pads pack bulkier than air pads, so they suit trips where the car carries the weight.

Winter and cold ground

Below about 20°F, REI's guide calls for R 4–5.4, and 5.5 or higher for extreme cold. The R-Value 9.0 Insulated Pad is OGERY's cold-weather pad and the only pad on this site with an R-value in its product name. OGERY lists it at R-Value 9.0, with multi-layer reflective insulation, about 4.7" thickness, 40D nylon with a TPU coating, and a pump bag for inflation. The inflated size is about 70.8" × 24", and it packs to about 5.5" × 5.5" × 8.3" at roughly 2.5 lb. It's marketed for four-season and winter camping.

Two practical notes. First, R 9.0 is well above REI's 5.5 threshold for extreme cold. The product details we have don't name the test method behind the figure, so if you're comparing it number for number with pads rated to ASTM F3340, check the Amazon page for the method first. Second, the pump bag fits REI's advice for cold trips: inflating with a pump sack instead of your breath keeps moisture out of the pad. A high-R pad is also only half the system. Pair it with a bag rated for the night, since the pad isn't a sleeping bag.

Real-world factors the number doesn't cover

• Stacking adds up. Per REI, and confirmed by Therm-a-Rest's engineers in the SectionHiker interview, R-values are additive when two pads sit together with no air gap. A pad rated 2 on top of one rated 3 gives about 5. REI suggests putting a closed-cell foam pad under an inflatable one in winter for insulation, puncture protection and a backup. You can only do this math with pads that publish a number, though.
• Cold air softens air pads. REI notes that air pads lose pressure as temperatures drop, so top up the firmness right before bed. Therm-a-Rest's engineers guessed that letting some air out might cut R-value by 5–10%, and they were clear it was only an estimate.
• Moisture matters over time. REI says breath moisture trapped inside an air pad can eventually degrade performance or lead to mold. A pump or pump sack helps, and so does storing the pad unrolled with the valves open.
• Fit matters. A pad narrower than your shoulders leaves arms and elbows on the tent floor. REI notes most pads are about 20" wide and 72" long, with wider and longer options for restless or taller sleepers. OGERY's 6" pad (about 27.5" wide) and R9.0 pad (about 24" wide) are both wider than that typical 20".

Reading an R-value on a product page

1. Look for the test method. "R-value 4.2 (ASTM F3340)" can be compared across brands. A bare number may not be.
2. Match it to your coldest night, not your average one, using the season table above.
3. Check the bag assumption. If your pad is below R 4, expect your bag to feel cooler than its rating.
4. Don't read R-value into thickness. A thick pad without a published R-value is a comfort pad until proven otherwise.

FAQ

Is a higher R-value always better? For warmth, yes. The trade-offs are weight, packed size and cost, which is why REI suggests choosing the two qualities you care about most. On hot summer nights, a very high R-value simply isn't needed.

Can I use a summer pad in winter? You can add a second pad underneath to raise the total, since R-values add up. Without a published number for the summer pad, though, you can't calculate the total with confidence.

Does a thicker pad mean a warmer pad? Not necessarily. Therm-a-Rest's engineers list chambers, reflective layers and foam, not thickness alone, as what drives R-value. OGERY's thinner R9.0 pad (about 4.7") is the one with an R-value in its product name, while the thicker 6" pad's name and feature bullets give none.

Why doesn't every pad have an R-value? Testing to ASTM F3340 needs specialized equipment. SectionHiker's interview put one commercial test machine at about $50,000, which is one reason not every brand publishes a rated figure for every pad.

Where to go next

If you're deciding between OGERY's two inflatable pads, 6" Ultralight Pad vs R-Value 9.0 Pad: Which OGERY Pad Fits? compares them spec by spec, and the OGERY 6" Ultralight Pad review covers the comfort pad in more depth. For the full range, see How to Choose OGERY Sleeping Pads, Fans & Camping Gear and the OGERY review, or browse OGERY Foam & Inflating Sleep Pads, OGERY Insulated & Self-Inflating Pads and OGERY Kids Sleeping Bags.

The short answer: under R 2 for warm nights, 2 to 4 for spring and fall, 4 and up for winter, and when the number matters, make sure it was measured to ASTM F3340.

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