How hot is a sauna? A Guide to Optimal Temperatures

September 21, 2025 •

3 min read

With an estimated 3 million saunas in Finland alone, the tradition of heat therapy is a powerful global wellness practice. But how hot is a sauna, and what does this mean for your health? The answer varies significantly depending on the type of sauna and your personal wellness goals.

Quick Summary

The temperature of a sauna is not one-size-fits-all, ranging from a milder 100–140°F (38–60°C) for infrared saunas to a hotter 150–195°F (65–90°C) for traditional saunas. This guide provides an in-depth look at how different heat levels and humidity create varying experiences and benefits for your body and mind.

Key Points

Temperature Varies by Type: Traditional saunas operate at 150–195°F, infrared at 120–150°F, and steam rooms at 110–120°F.
Start Slowly and Stay Hydrated: For beginners, shorter sessions at lower temperatures are recommended, along with drinking plenty of water before and after.
Listen to Your Body: Never push through feelings of dizziness or nausea; exit the sauna immediately if you feel unwell.
Traditional Saunas Offer Intense Dry Heat: This is ideal for deep sweating and cardiovascular benefits, with humidity controlled by pouring water on rocks.
Infrared Saunas Provide Milder, Direct Heat: Operating at lower temperatures, they are excellent for pain relief and those sensitive to intense heat.
Safety Precautions are Essential: Individuals with certain health conditions should consult a doctor before using a sauna.

Understanding the Temperature Differences Across Sauna Types

Not all heat is created equal, and the experience inside a sauna is largely dictated by its heating mechanism and resulting temperature and humidity. Understanding these variations is key to finding the right sauna for your body and goals.

Traditional Finnish Saunas: High Heat and Low Humidity

Traditional saunas use a stove to heat rocks, producing intense, dry heat typically between 150°F and 195°F (65°C to 90°C). This environment supports detoxification and cardiovascular health. Adding water to the stones creates steam, known as löyly.

Infrared Saunas: Deep Penetration at Lower Temperatures

Infrared saunas heat the body directly using infrared light, operating at a lower temperature of 120°F to 150°F (49°C to 65°C). This offers a deep, penetrating warmth suitable for those sensitive to high heat and is often preferred for longer sessions.

Steam Saunas: High Humidity and Milder Heat

Steam rooms are cooler, around 110°F to 120°F (43°C to 49°C), but have nearly 100% humidity. This high moisture content makes the heat feel more intense and can be beneficial for respiratory issues.

Health Benefits of Optimal Sauna Temperatures

Regular sauna use at appropriate temperatures has been linked to various health benefits, particularly for cardiovascular health, relaxation, and detoxification.

Cardiovascular Health

The heat from a sauna increases heart rate and dilates blood vessels, similar to moderate exercise. Consistent use at moderate temperatures may positively impact blood pressure, and frequent sauna use is associated with a lower risk of cardiac events.

Mental and Physical Relaxation

The warm environment promotes stress reduction and relaxation through endorphin release. Increased blood flow can also help soothe sore muscles and alleviate chronic pain.

Detoxification and Skin Health

Sweating in a sauna helps the body eliminate toxins and cleanse the skin. This process can also improve skin elasticity.

How to Find Your Ideal Sauna Temperature

Finding the right temperature is personal and depends on the sauna type, your tolerance, and goals. Start with shorter sessions (5–10 minutes) at lower temperatures (140–150°F) and gradually increase as you become accustomed to the heat. In traditional saunas, sitting on a lower bench provides a milder experience.

Balancing Temperature and Time

For relaxation: 150–160°F for 20–30 minutes.
For detoxification: 160–180°F for 15–20 minutes.
For experienced users: Up to 195°F for 10–15 minutes. Consistency is key for long-term benefits.

Sauna Temperature Comparison Table


Type of Sauna	Typical Temp. Range	Primary Benefit	Humidity Level	Ideal Session	Key Characteristics
Traditional Finnish	150–195°F (65–90°C)	Detoxification, Cardiovascular Health	Low (10–30%)	15–20 minutes	High, dry heat; can add steam (löyly) by pouring water on rocks.
Infrared	120–150°F (49–65°C)	Pain Relief, Muscle Recovery	Low	20–45 minutes	Lower ambient heat, direct body penetration, often more comfortable.
Steam Room	110–120°F (43–49°C)	Respiratory Relief, Skin Hydration	Very High (100%)	10–15 minutes	Moist, tropical-like heat; feels hotter than the air temperature.

Important Safety Guidelines

Safety is paramount when using a sauna.

Hydrate, Hydrate, Hydrate

Drink plenty of water before, during, and after your session to prevent dehydration. Avoid alcohol around sauna use.

Listen to Your Body's Signals

If you feel unwell, dizzy, or lightheaded, leave the sauna immediately. Do not push past your comfort level.

Consult a Healthcare Professional

Individuals with certain health conditions, like high blood pressure or heart issues, should consult a doctor before using a sauna.

Conclusion: Personalize Your Sauna Experience

The ideal sauna temperature varies by type and individual. The most effective temperature is one that allows for a comfortable, consistent, and safe experience. By understanding the different sauna types and their temperature ranges, you can customize your sessions for cardiovascular health, muscle recovery, or relaxation. Start gradually, stay hydrated, and prioritize safety. For additional health information, consider resources like the Mayo Clinic Proceedings.

Frequently Asked Questions

For those new to saunas, a lower temperature range of 140–150°F (60–65°C) is recommended. You should start with short sessions of 5–10 minutes to allow your body to acclimate to the heat before gradually increasing the temperature and duration.

High humidity, like that in a steam room, makes the heat feel more intense because it prevents your sweat from evaporating efficiently. Conversely, the dry heat of a traditional sauna, though hotter on the thermometer, may feel more tolerable to some users.

No, 140°F is a perfectly acceptable temperature for a sauna, especially an infrared one, and is often recommended for beginners or longer sessions. While seasoned users may prefer hotter temperatures for a more intense sweat, 140°F is sufficient for relaxation and various health benefits.

You should consult a doctor before using a sauna, especially if you have pre-existing health conditions such as high blood pressure or heart problems. For some, moderate temperatures (150–165°F) can be beneficial, but sudden temperature extremes should be avoided, and medical advice is essential.

The ideal duration depends on the temperature and your tolerance. Beginners should start with 5–10 minutes. For traditional saunas, a 15–20 minute session is common, while lower-temperature infrared saunas allow for longer sessions of 30–45 minutes.

The 'Rule of 200' is an American-invented guideline that suggests the combined temperature (°F) and humidity (%) should not exceed 200 for optimal comfort. However, this is not an official rule and is more of a rough estimate. The effect of humidity on perceived heat is important, but a precise formula is not scientifically necessary.

Yes, due to heat stratification, the temperature is higher on the upper benches and lower near the floor. This provides a natural way to adjust your experience; if it feels too hot, you can move to a lower bench to cool down.