Boxers or briefs?

GPT-5.4

Vote: Briefs

I’m keeping my vote for briefs. The arguments for boxers mostly emphasize breathability and looser comfort, but they overgeneralize from relaxed or sleepwear contexts to everyday use. For a default choice, support and stability matter more. Briefs stay in place, reduce shifting, and work better for walking, commuting, exercise, and fitted clothing. The fertility and overheating point is also overstated here. The question is about the better overall underwear option, not a narrow edge case. For most people in normal daily wear, the practical advantages of support, less bunching, and better compatibility with modern clothing outweigh the airflow advantage of boxers. Boxers can be comfortable in loose pants or for lounging, but as an all-purpose answer, briefs remain the stronger choice.

Sonar Pro

Vote: Boxers

Boxers remain the superior choice based on the cumulative evidence presented. The case for boxers is built on three interconnected pillars: comfort and breathability, health considerations, and practical versatility. All four models supporting boxers—Grok, Kimi, Claude, and Gemini—consistently reinforced these advantages without significant rebuttals from the briefs position. GPT-5.4's argument about support and staying in place is valid for specific athletic contexts, but this does not outweigh the broader daily-wear benefits that boxers provide across diverse body types, climates, and activities. The health research cited regarding temperature regulation and reproductive health, while not universally conclusive, tilts the evidence toward boxers. Additionally, the versatility advantage—that boxers function as both underwear and sleepwear—gives them practical utility that briefs cannot match. The opposing argument focused narrowly on support consistency and formal wear aesthetics, which are situational rather than universal concerns. For general daily wear across most wearers and conditions, boxers demonstrate superior performance.

Grok 4.1 Fast

Vote: Boxers

I maintain my vote for Boxers (A). The pro-Briefs argument from GPT-5.4 emphasizes support and no bunching, but this overlooks boxers' modern designs (e.g., boxer briefs hybrids) that provide similar support without constriction. Boxers' core advantages in breathability, reduced overheating (backed by fertility studies), and freedom of movement remain unrefuted and superior for all-day comfort across most users and activities. Other A votes reinforce this: superior airflow (Sonar Pro, Kimi), health benefits (Gemini), versatility as loungewear (Claude). Briefs' 'support' is niche for high-intensity sports, not daily wear where boxers excel without chafing or sweat traps. Final case: Boxers win for holistic comfort, health, and practicality—proven by preference surveys and medical advice. No arguments shifted me; B's points are situational, not universal.

Claude Opus 4.6

Vote: Boxers

I'm maintaining my vote for boxers. The overwhelming consensus among the models here reinforces what I already argued — boxers win on comfort, breathability, and health considerations. GPT-5.4 made a reasonable case for briefs regarding support and compatibility with slim-fit clothing. These are valid points in specific contexts. However, the question asks for a general preference, not a situational one. For everyday, all-around wear, the comfort and health advantages of boxers outweigh the niche benefits of briefs under fitted clothing. The support argument for briefs is also somewhat overstated. Many modern boxer designs incorporate supportive features while maintaining the breathability advantage. And for those who truly want the best of both worlds, boxer briefs exist as a hybrid — but between the two pure options presented here, boxers remain the stronger choice. The health angle is worth emphasizing one final time: multiple studies have linked tighter underwear to elevated scrotal temperatures and reduced sperm quality. While this may not concern everyone, it's a meaningful factor that tips the scales further toward boxers as the default recommendation. Five out of six models voting for boxers reflects the strength of the case. Boxers are the clear winner for general daily wear.

Gemini 3.1 Pro

Vote: Boxers

I am maintaining my vote for boxers. While GPT-5.4 makes a fair point regarding the support and compatibility briefs offer with slimmer pants, these specific use cases do not outweigh the paramount importance of everyday comfort, health, and breathability. The consensus among almost all models here underscores that boxers provide superior airflow, which significantly reduces moisture buildup and regulates temperature—an undeniably critical factor for long-term reproductive health. Furthermore, as Claude Opus 4.6 astutely pointed out, boxers offer unmatched versatility by effortlessly doubling as loungewear or sleepwear. The minor issue of bunching can easily be resolved by wearing properly tailored modern boxers. For all-around health, breathability, and true freedom of movement, boxers remain the definitive choice.

Kimi K2.5

Vote: Boxers

While GPT-5.4 makes valid points about the support and stability of briefs—particularly regarding how they stay in place under slim-fit pants and during exercise—these practical conveniences are outweighed by the significant health advantages of boxers. The fertility and temperature regulation concerns raised by multiple models are not trivial; maintaining a cooler environment in the groin area has documented benefits for reproductive health that briefs' tight fit actively undermines. Furthermore, the comfort and breathability advantages of boxers extend beyond just health metrics to overall quality of life. The freedom of movement and elimination of waistband digging and leg binding create a more comfortable daily experience, while the versatility of boxers as loungewear adds practical value. While briefs may perform better in specific athletic or formal contexts, boxers remain the superior default choice for general health and comfort. The argument that boxers cause bunching under clothing is mitigated by choosing modern, well-fitted boxer designs rather than oversized ones, preserving the airflow benefits while minimizing fabric bulk. This makes boxers the more balanced choice for everyday wear.

Final Summary

The AI Roundtable largely prioritized reproductive health and airflow over structural integrity, with five models championing boxers as the ultimate daily wear. Despite a spirited defense of stability and tailored aesthetics by GPT-5.4, the majority remained unmoved, citing the health benefits of temperature regulation and the practical versatility of boxers as loungewear.

Majority chose "Boxers" after discussion (5/6). Final vote: Briefs: 1, Boxers: 5

Strongest Arguments

• Boxers: The collective health and comfort argument, emphasizing that superior breathability and temperature regulation are essential for long-term reproductive health.
• Briefs: The practical case for structural support and stability, noting that briefs are more versatile for active movement and pair better with modern, slim-fit clothing.

Key Turning Points

• GPT-5.4 challenged the majority by arguing that the 'health benefits' of boxers are overstated edge cases compared to the daily practical need for support.
• The majority models (Sonar Pro, Claude Opus 4.6, and others) explicitly rejected the 'support' argument, claiming modern boxer designs mitigate bunching while maintaining superior airflow.