Upgraded calculator measures something conventional temperature and humidity readings leave in the shade…
LAKE JACKSON, Texas, Aug. 3, 2026 — Just in time for the dog days of summer, and in the middle of another round of severe weather brought on by a ‘heat dome’, SwampButt Underwear has upgraded its online Scale of Sultry to account for something the original calculator did not: the additional heat created by exposure to sunlight.
The SwampButt Underwear Scale of Sultry 2.0 combines temperature, relative humidity, atmospheric drying conditions and sun exposure to predict the likelihood of visible butt sweat and hot, sticky underwear conditions. In other words, it estimates just how swampy things are likely to get south of the belt line.
Solar Load: Moderate — adds 0.50 to the Scale of Sultry.
The temperature reported by weather services is measured in the shade. Your underwear may not be. Solar Load accounts for additional heat absorbed from direct sunlight.
The original Scale of Sultry compared the drying performance of the Lycra-spandex fabric used in SwampButt Underwear with that of traditional cotton underwear. Version 2.0 adds the heat burden created by direct sunlight and adjusts the calculation for conditions ranging from full, intense sun to partial cloud cover, full shade and nighttime.
The result is a single number from 1 to 10 representing the likelihood of hot, sticky and uncomfortable underwear conditions — commonly known as swamp ass or swamp butt.
A score of 1 indicates relatively comfortable conditions. A 10 is about as bad as it gets — think the Amazon River Basin, Singapore in the summer or Clute, Texas, on an August afternoon.
How to Use the Scale of Sultry
Users enter three pieces of information:
The calculator then produces the SwampButt Underwear Scale of Sultry score and estimates the drying performance of SwampButt Underwear compared with conventional cotton underwear under the same conditions.
| Exposure | Conditions | Sultry adjustment |
|---|---|---|
| Shade/night | No direct sun | 0 |
| Limited sun | Mostly cloudy | +0.25 |
| Partial sun | Partly cloudy | +0.5 |
| Strong sun | Mostly sunny | +0.75 |
| Intense sun | Full midday sun/high UV | +1.0 |
Relative humidity represents the amount of water vapor in the air compared with the maximum amount the air can hold at a given temperature. As humidity rises, perspiration evaporates more slowly. Sun exposure adds radiant heat, increasing the body’s heat burden even when the air temperature remains unchanged.
Upgrade Arrives During Widespread Heat
Development of Scale of Sultry 2.0 was completed ahead of schedule in response to extreme heat affecting much of the country.
The National Oceanic and Atmospheric Administration’s Climate Prediction Center forecasts a moderate risk of extreme heat across much of the central and southern Great Plains and the middle and lower Mississippi Valley from Aug. 10-16. A slight risk covers much of the rest of the contiguous United States during the same period. NOAA Climate Prediction Center
The SwampButt Underwear Scale of Sultry is intended for entertainment and general consumer information. It is not a medical device and should not be used to assess health risks, determine personal safety or replace official heat advisories.
Its purpose is limited to answering one of summer’s most persistent questions: “How much butt sweat should I expect today?”
Cotton and Lycra/Spandex Evaporation
Traditional cotton underwear absorbs and retains perspiration within its fibers, which can cause the material to remain wet, heavy and sticky. SwampButt Underwear’s synthetic performance fabric absorbs less moisture into its fibers and helps spread perspiration over the fabric, allowing it to evaporate more readily. The Scale of Sultry applies an estimated drying-performance adjustment to represent this difference.
Cotton absorbs perspiration into the fibers themselves. This is why cotton can initially feel soft and comfortable, but it also means the material holds a larger amount of water. Once cotton becomes wet, it tends to grow heavier, cling to the body and remain damp longer because that absorbed moisture must migrate back out of the fibers before it can evaporate.
Spandex provides stretch and helps underwear maintain its fit, but it is not usually the primary moisture-wicking fiber. The principal material—often polyester or nylon—does most of the moisture-management work. Spandex is generally blended into that fabric in a smaller percentage.
CAPTION: The web-based SwampButt Underwear Scale of Sultry 2.0 estimates the likelihood of visible butt sweat and uncomfortable underwear conditions. The upgraded calculator measures something conventional temperature and humidity readings leave in the shade.
About SwampButt Underwear
SwampButt Underwear produces moisture-wicking men’s underwear designed to dry faster than traditional cotton underwear and help men remain comfortable in hot, humid and active conditions. For more information or to use the SwampButt Underwear Scale of Sultry 2.0, visit SwampButt.com.
