How to Dress Your Baby for Sleep: A Simple Temperature Guide

Dressing a baby for sleep sounds trivial until you are standing over the crib at midnight wondering if they are too hot, too cold, or just right — and knowing that getting it wrong matters, because overheating is a genuine safety concern. The good news: there is a simple system. Here is how to dress your baby for sleep safely at any temperature, what TOG means, and how to read your baby's own signals.

The golden rule: not too hot

Before layers and TOG, the single most important principle: babies should not get too warm when they sleep, because overheating is a risk factor for SIDS. When in doubt, err on the side of slightly cooler rather than warmer. A comfortably cool room and appropriate light layers are safer than a bundled-up, overheated baby.

The recommended room temperature for baby sleep is around 16–20°C (about 68°F) — cooler than many people expect. You do not need to keep the nursery warm.

The simple layering rule

A handy guideline: dress your baby in one more layer than you would wear to be comfortable in the room — no more. For a baby, a "layer" might be a bodysuit, a sleeper, or a sleep sack. The aim is comfortable warmth, not cozy heat.

Use the table as a starting point and adjust to your baby and your home — every house and baby is a little different.

What is a TOG rating?

TOG is simply a measure of how warm a sleep sack or swaddle is — the higher the number, the warmer it is. It takes the guesswork out of layering:

• 0.5 TOG — lightweight, for warm rooms/summer
• 1.0 TOG — all-purpose, for typical room temperatures
• 2.5 TOG — warm, for cooler rooms/winter

Match the TOG to your room temperature (sleep sacks usually include a guide), and pair it with the right clothing layer underneath. A TOG-rated sleep sack makes dressing for sleep almost foolproof.

Sleep sacks and swaddles

• Sleep sacks (wearable blankets) are the safe modern alternative to loose blankets, which should never go in a crib. They keep your baby warm without any loose bedding — a win for both warmth and safe sleep.
• Swaddles suit newborns who like to be snug, but stop swaddling as soon as your baby shows any signs of rolling (usually around 8 weeks or so), switching to a sleep sack that allows arm movement. A swaddled baby who rolls is a safety risk. See how to swaddle a baby.
• No loose blankets, quilts, or duvets for babies — a sleep sack replaces them entirely.

How to tell if your baby is too hot or too cold

Forget their hands and feet — babies' extremities are often cool even when they are perfectly warm, so cool hands are not a reliable sign. Instead:

• Feel the chest, back of the neck, or tummy. These should feel comfortably warm — not hot and sweaty, not cold.
• Signs of overheating: sweating, damp hair, flushed cheeks, rapid breathing, or feeling hot to the touch on the chest/neck. Remove a layer.
• Signs of being too cold: a genuinely cold chest or tummy (not just cool hands). Add a layer.

If your baby feels hot, take a layer off — overheating is the one to avoid most.

A few more safety notes

• No hats indoors for sleep — babies release heat through their heads, and hats can cause overheating.
• Keep the crib bare — the sleep sack is the only "bedding" needed.
• Dress for the room, not the season — a warm night in a cool, air-conditioned room needs different layers than the thermostat suggests.
• Check on a very hot night — offer extra feeds for hydration and use the lightest safe layers.

Adjusting through seasons and travel

The layering system stays the same, but the numbers shift with your circumstances, so re-check rather than running on autopilot. In summer, especially without air conditioning, a hot nursery may call for nothing more than a bodysuit and a 0.5 TOG sack — and on the hottest nights, a diaper and a light sack alone. In winter, warm the room to the safe range rather than piling on extra layers or blankets, and reach for a higher-TOG sack over a footed sleeper. Air conditioning and fans matter too: a baby sleeping in a cool, air-conditioned room in summer may actually need a warmer layer than the outdoor weather suggests, so dress for the room, not the forecast. When traveling, hotel rooms and grandparents' houses run at unfamiliar temperatures — pack a couple of different sack weights and check your baby's chest on the first night in a new place. A cheap room thermometer (many baby monitors include one) takes the guesswork out of all of this and is well worth having. Whatever the season, the safety principle never changes: cooler is safer than too warm.

Frequently asked questions

What should my baby wear to sleep?

Dress your baby in about one more layer than you would wear to be comfortable in the room, using a TOG-rated sleep sack over a bodysuit or sleeper. Aim for comfortably warm, not hot, and keep the room around 16–20°C (about 68°F).

What is a TOG rating for sleep sacks?

TOG measures how warm a sleep sack is — 0.5 TOG for warm rooms, 1.0 for typical temperatures, and 2.5 for cooler rooms. Matching the TOG to your room temperature makes dressing for sleep almost foolproof.

How do I know if my baby is too hot?

Feel their chest, tummy or the back of the neck — not their hands and feet, which are normally cool. Sweating, damp hair, flushed cheeks or a hot chest mean they are too warm; remove a layer, since overheating is a safety risk.

Can my baby sleep with a blanket?

No — loose blankets are not safe in a crib for babies. Use a wearable sleep sack instead, which keeps your baby warm without any loose bedding. This protects both warmth and safe sleep.

The takeaway

Dressing your baby for sleep comes down to one principle — do not let them overheat — plus a simple system: dress them in one more layer than you would wear, use a TOG-rated sleep sack matched to a cool room (around 16–20°C), and skip loose blankets and indoor hats entirely. Check warmth on the chest or neck, not the hands, and remove a layer at any sign of overheating. Get this right and your baby sleeps safely and comfortably. For the full sleep-safety picture, see safe sleep guidelines.

*This article is general information, not medical advice. Follow safe-sleep guidance and talk to your pediatrician with any concerns.*