Set this to your room's temperature
Some recommended items may not be in your wardrobe — consider dressing for the cooler temperature now.
Tip: choose the bag for the coldest the room will get tonight, but clothing for how warm it is now — so they aren’t over-wrapped early on.
Some recommended items may not be in your wardrobe — check you have a lighter option ready.
Tip: if the room may warm up later, err lighter on clothing — layers can’t come off once they’re asleep, while the bag still keeps them warm if it cools again.
Tap the items you own — the recommendation adapts to your wardrobe.
See tonight's outdoor temperature to anticipate how the room may change. Your location is sent only to the weather service to fetch the forecast — it is not stored.
| Room | Bag | Wear |
|---|---|---|
| Above 27°C | No bag — too warm | Nappy or a light vest only |
| 24–27°C | 0.5 TOG | Sleeveless bodysuit |
| 22–23.9°C | 1.0–1.5 TOG | Short-sleeved bodysuit |
| 20–21.9°C | 1.5 TOG | Long-sleeved bodysuit |
| 18–19.9°C | 1.5–2.5 TOG | Short-sleeved bodysuit and a sleepsuit (or full pyjamas) |
| 16–17.9°C | 2.5 TOG | Short-sleeved bodysuit and a sleepsuit (or full pyjamas) |
| 13–15.9°C | 2.5–3.5 TOG | Long-sleeved bodysuit and a sleepsuit (or full pyjamas) |
| Below 13°C | 3.5 TOG | Long-sleeved bodysuit, a sleepsuit and an extra warm layer on top — and warm the room toward 16–20°C |
16–20°C is the NHS / Lullaby Trust ideal range
See the chart for a specific temperature →TOG stands for Thermal Overall Grade — it measures how warm a sleeping bag or duvet is. The higher the TOG rating, the warmer the bag.
At 18–20°C, most guides recommend a 1.5–2.5 TOG bag with a short-sleeved bodysuit and a sleepsuit (or full pyjamas) underneath. This sits within the NHS and Lullaby Trust's recommended 16–20°C range for safe sleep.
A 2.5 TOG bag can run a little warm at 20–21°C — 1.5 TOG is the closer match for that band. If you only have a 2.5 TOG bag, drop to lighter layers underneath and check your baby's chest or the back of their neck for signs of overheating.
Above 27°C, overheating risk is significant — removing the sleeping bag entirely is often the safest option, with just a nappy or a light vest while the room stays this warm. Keep checking your baby isn't hot or sweaty and cool the room if you possibly can.
Feel their chest or the back of their neck — not their hands or feet, which are normally cool. Remove a layer if they feel hot or sweaty, and add a layer or warm the room if they feel cold.
No — the NHS and The Lullaby Trust advise against using a cot duvet or loose blanket with a sleeping bag, as this raises the risk of overheating. Choose a bag with the right TOG for the room instead.