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In this guide
A baby sleeping bag keeps your baby warm without loose blankets, and the TOG rating tells you how warm it is. Picking the right TOG for the temperature of the room is the single most useful thing to get right, and it's simpler than it looks.
What TOG means
TOG (thermal overall grade) measures how well a fabric holds in heat. The higher the number, the warmer the bag. Baby sleeping bags usually come in four ratings:
- 0.5 TOG: very light, for hot rooms and summer nights.
- 1.0 TOG: light, for warm rooms.
- 2.5 TOG: the all-rounder, for a typical UK bedroom most of the year.
- 3.5 TOG: extra warm, for cold rooms in winter.
The TOG is for the bag alone. What your baby wears underneath matters just as much, which is why charts always pair a TOG with clothing.
The right temperature for a baby's room
The Lullaby Trust advises keeping the room your baby sleeps in at 16–20°C. Babies who get too hot are at higher risk of sudden infant death syndrome (SIDS), so it's better to be slightly cool than too warm. A simple room thermometer takes the guesswork out of it, and many baby monitors show the temperature too.
TOG chart: what to use and what to dress them in
This is the guidance most UK sleeping bag makers give. Always check the chart on your own bag's label, as brands vary slightly.
| Room temperature | Sleeping bag | Underneath |
|---|---|---|
| 24°C or more | 0.5 TOG, or no bag | Nappy, or a short-sleeved bodysuit |
| 21–23°C | 1.0 TOG | Short-sleeved bodysuit, or a light sleepsuit |
| 16–20°C | 2.5 TOG | Long-sleeved bodysuit, or a sleepsuit |
| 15°C or less | 3.5 TOG | Long-sleeved bodysuit and a sleepsuit |
If you only buy one, a 2.5 TOG bag covers most UK homes for most of the year. Add a 1.0 TOG for summer, and you're set.
