A baby TOG calculator built around safer-sleep advice
What should my baby wear to bed, and is the nursery too warm? This baby TOG calculator takes the temperature of the room where your baby sleeps, compares it with the 16–20 °C that the Lullaby Trust recommends, and shows the sleep-bag tog and clothing that the labels on many sleep bags suggest for that temperature. A second tab checks bath water against the usual 37–38 °C.
The tog bands are a typical guide, not a rule: the Lullaby Trust deliberately does not publish a tog chart, because fabrics, layers and babies all differ. So this page always points you back to your own sleep bag’s label and to the simplest check of all — feeling your baby’s chest or the back of the neck.
This page is information only, not medical advice. No chart prevents sudden infant death syndrome (SIDS); keeping your baby from overheating is one of several safer-sleep steps that lower the risk.
How to use the Baby Room Temperature & TOG Guide
- Choose °C or °F.
- Enter the room temperature from a room thermometer placed near the cot.
- Read the typical sleep-bag tog and layers, and the note on how the room compares with 16–20 °C.
- Check the label on your own sleep bag, then feel your baby’s chest or the back of the neck once they are settled.
- At bath time, open Bath water and enter the reading from a bath thermometer.
Baby Room Temperature & TOG Guide features
Room check
Compares the room with the Lullaby Trust’s recommended 16–20 °C, with a coloured scale and plain advice for cool and warm rooms.
Tog rating chart
The five generic bands found on many sleep-bag labels, with typical clothing underneath.
Bath water check
Cool, within, or warmer than about 37–38 °C, with the NHS safety reminders.
°C and °F
Switching converts what you have typed.
Safer-sleep summary
The key Lullaby Trust messages on the same page.
Tog rating chart (typical label guide)
Tog is a measure of warmth: the higher the number, the warmer the product. Brands print slightly different bands, and the same tog can feel different in different fabrics, so treat this as a starting point. Two 1.0 tog sleep bags do not simply make 2.0 tog — trapped air adds warmth — so do not layer bags, and do not add blankets on top of a sleep bag.
| Room temperature | Typical sleep-bag tog | Typical clothing under it |
|---|---|---|
| Below 16 °C (61 °F) | 3.5 tog | Long-sleeved bodysuit and a sleepsuit |
| 16–20 °C (61–68 °F) | 2.5 tog | Bodysuit and a sleepsuit |
| 21–23 °C (69–75 °F) | 1.0 tog | Short-sleeved bodysuit and a sleepsuit, or a long-sleeved bodysuit |
| 24–27 °C (75–81 °F) | 0.5 tog | Short-sleeved bodysuit |
| Above 27 °C (81 °F) | 0.2 tog or no sleep bag | Just a short-sleeved bodysuit or a nappy |
Room temperature for baby sleep
The Lullaby Trust recommends 16–20 °C so that babies do not get too hot, and says keeping the room in this range where possible helps lower the risk of SIDS. Use a room thermometer, as rooms are often warmer or cooler than they feel. In cold weather it is rarely necessary to keep the heating on all night; if you do, keep it low and no higher than 20 °C, and keep the cot away from radiators. In hot weather, use lighter bedding and clothing, open a window or door if it is safe, and use a fan only if it is not aimed at your baby.
To check your baby, feel the chest or the back of the neck — hands and feet are usually cooler, which is normal. If the skin is hot or sweaty, remove a layer; if your baby feels cold, add a layer of clothing or use a higher-tog bag. Babies do not need hats indoors.
Baby bath temperature range
NHS newborn bathing guidance gives approximately 37–38 °C (about 98.6–100.4 °F), checked with a bath thermometer or by the elbow test — the water should feel comfortably warm. Mix the water well so there are no hot patches, warm the room first, and never leave your baby alone in the bath, even for a second. For a baby who seems feverish, the fever temperature checker explains readings, and the baby sleep schedule helps with naps and bedtimes.
Baby Room Temperature & TOG Guide FAQ
What is the right room temperature for a baby to sleep?
The Lullaby Trust recommends 16–20 °C (about 61–68 °F). The baby TOG calculator shows where your room sits in that range.
What tog sleeping bag should my baby use?
Many labels suggest about 2.5 tog at 16–20 °C, 1.0 tog at 21–23 °C and 0.5 tog at 24–27 °C. Always follow your own sleep bag’s label and check your baby’s chest or the back of the neck.
Does the Lullaby Trust have a tog chart?
No. It explains that it does not give a tog chart because products, layers and babies differ; it recommends 16–20 °C, light bedding or a well-fitting sleep bag, and checking your baby.
What temperature should a baby’s bath be?
About 37–38 °C (98.6–100.4 °F). Mix well, test with your elbow or wrist too, and never leave your baby alone in the bath.
Should my baby wear a hat to sleep?
Not indoors. Babies lose heat through their heads, and a covered head can make them overheat.
Can a tog chart prevent SIDS?
No. Avoiding overheating is one safer-sleep step among several — back to sleep, a clear cot, the same room for the first six months, and a smoke-free home all matter.