How to use a sauna: temperature, timing and safety

How to use a sauna, step by step

The method is straightforward once you know the order. If you have just bought or are about to try a home sauna, whether that is a barrel or outdoor cabin, a garden sauna or an infrared sauna, this is the whole routine:

1. Heat the sauna to temperature before you go in. Heat-up time varies by type, and a barrel sauna is one of the quickest.

2. Drink a glass or two of water beforehand, and take a towel to sit on.

3. Get in and sit for a short first round, keeping to the beginner time in the box below.

4. Come out, cool down, rest and rehydrate, then go back in for another round if you want one.

5. Finish, cool down properly and drink more water. The traditional way to end is on cold, which is where contrast therapy comes in.

The rest of this guide takes each step in turn: how hot to set it, how long to stay in, how many rounds, hydration, what to expect and the beginner mistakes to avoid. The safety section near the end matters most of all, so read it before your first session.

How hot should a sauna be?

This is the question most people start with, and the answer depends entirely on the type of sauna. The right sauna temperature is not a single number but a range that differs between the two main types.

A traditional or outdoor sauna heats the air with a stove and a pile of stones, giving a hot, dry heat that you can soften with steam. An infrared sauna works in a completely different way: its panels warm your body directly rather than heating the air around you, so it feels comfortable at a much lower temperature. That is why infrared saunas run far cooler than traditional ones, and why many beginners find them easier to tolerate.

Neither type is better than the other. A traditional sauna gives the intense, classic Finnish heat and the option of löyly steam; an infrared sauna is gentler and often easier to fit and run indoors. The temperature to set each type is in the box below, and those are the numbers to work to whichever you own.

How long should you stay in, and how many rounds?

Start short and build up. First sessions should be brief, and as you get used to the heat you can extend them a little, but there is a sensible ceiling beyond which you gain nothing and raise the risk of overheating and dehydration. Treat the upper limit as a hard stop, not a challenge.

Most people do a few rounds, each followed by a cool-down. Between rounds, come out, cool down and let your heart rate settle before going back in. A cool shower or a few minutes of fresh air works well. The exact figures, how long per round, how many rounds and how long to cool down for, are in the box below.

The temperatures and times to work to

Here are the ranges to work to for temperature, session length, rounds and cooling down. Treat them as a sensible starting point tied to the evidence, not as targets to beat, and build up gradually.

What to expect in your first session

Your first sauna can feel intense, and that is normal. You will warm up quickly, start sweating within a few minutes and feel your heart rate rise, much as it would during light exercise. That heart-rate response is expected, and it is also part of why the safety section matters.

Keep your first visit short and calm. Sit or lie down, breathe steadily, and come out if you feel dizzy, faint, sick or simply too hot. You should feel relaxed and warm afterwards, not drained or unwell. Over a handful of sessions the heat becomes far more comfortable and you can gradually build up your time.

Hydration: before and after

Heat makes you sweat, and sweating loses fluid, so hydration is part of the method rather than an afterthought. Drink water before you go in and again after each session to replace what you lose. The amounts to aim for are in the box above.

Do not drink alcohol before, during or after a sauna (see the safety section for why), and go easy at any point when you feel thirsty, light-headed or unwell.

Löyly: throwing water on the rocks

Löyly is the burst of soft steam you make by ladling water onto the hot stones of a traditional sauna. It lifts the humidity for a few moments and makes the heat feel more intense. Add it gradually, a little at a time, and be mindful of anyone sharing the sauna with you, because the steam affects everyone. The amount of water to use at once is in the box above.

Löyly applies to traditional saunas with a stove and stones only. An infrared sauna has no stones, so there is no water to throw and no steam.

What to wear, and can you take your phone in?

In a home sauna, wear a swimsuit or sit wrapped in a towel, and always put a towel down to sit on. Nudity is normal in Finland but it is a personal choice, and in a shared or family setting a swimsuit or towel wrap is the simplest option.

Leave your phone and smartwatch outside. Sauna heat is not kind to electronics, so it is safest to leave screens out of the cabin. Take off metal jewellery too, as it can get uncomfortably hot against the skin.

Finishing on cold: sauna and contrast therapy

The traditional way to end a sauna is on cold: a cool shower, a cold plunge or an ice bath. Alternating hot and cold like this is called contrast therapy, and it is the natural next step once you are comfortable with the sauna on its own.

Cold immersion has its own technique and its own safety rules, so build up to it gradually and read up before you start rather than jumping straight in. Our guide to sauna and cold plunge contrast therapy covers how to combine the two safely.

Should you sauna before or after a workout?

Both are common, and the right choice depends on your goal. After training, a sauna is a relaxing way to wind down, and many people value that sense of recovery. Before training, keep it brief, because the heat is tiring and dehydrating and a long session beforehand will not help your performance. Whenever you use it, hydrate well and never combine it with alcohol.

Beginner mistakes to avoid

• Setting it too hot. Start at the lower end of the range and build up. A hotter sauna is not a better one, and it is harder on your body.

• Staying in too long. Past the sensible ceiling in the box you add risk, not benefit. Build your time up over weeks.

• Drinking alcohol. Never use a sauna after drinking. Alcohol and sauna heat are a dangerous combination, as the safety section explains.

• Not hydrating. Drink water before and after. Skipping it is the quickest route to feeling dizzy or faint.

• Ignoring how you feel. Dizziness, nausea or feeling unwell means get out and cool down, not push on through.

Does a sauna have health benefits?

Sauna use is enjoyable and relaxing, and for most healthy people that is reason enough on its own. On the wider health claims, it pays to be honest about what the evidence actually shows.

The strongest finding is that regular sauna use has been associated with lower rates of heart disease and death in long-running Finnish studies. That is a genuine and encouraging link, but it is observational, which means it shows an association rather than proving the sauna caused the benefit, and it looked at traditional Finnish saunas. Treat it as promising rather than proven. Longer-term effects on blood pressure, stress, sleep and mood are plausible and under study, but not settled, so "may help" is the honest phrasing.

Two claims are worth pushing back on. A sauna does not "detox" your body: your liver and kidneys do that, and sweating does not meaningfully clear toxins. And it is not a weight-loss tool, because any weight you lose is water you sweat out, and it returns as soon as you rehydrate. For the fuller picture, see our sauna benefits guide.