Baby Sleep Sacks Warmth Chart

What is the thermal index of a textile (TOG rating)?

The TOG is a universal unit of measurement quantifying the thermal resistance of a product, i.e. the quantity of air that passes through the textile from the inside to the outside.

The higher the TOG is, the more warmth the sleeping bag will provide (warmer and cozier). The lower the TOG is, the more air the sleep sack will let through (lighter and more breathable).

   What is the ideal TOG for my baby? Expert advice

 Consider room temperature

What is the temperature of the baby's room at night and during naps?
In some families, the temperature is set around 66°F (19°C) at night, while in others the thermometer indicates 72°F (22°C) regardless of the time of day.

Between 61 and 68°F (16-20°C) choose a higher TOG sleep sacks
Available fabrics : Velour; 2.5 Togs Bamboo; Woven Cotton
Between 64 and 72°F (18-22°C) choose one of our universal sleep sacks
Available fabrics : Plush; 4 layers cotton; 1.0 Tog bamboo
Between 73 and 81°F (23-27°C) discover our lightweight sleep sacks
Available fabrics : Cotton muslin; Bamboo muslin

Identify the season the sleep sack will be worn

Just like us, it is possible that baby will prefer certain textiles over others depending on the season. In the fall, we often like to swap our cotton sheets for flannel sheets and in the spring, we easily opt for lighter sheet sets.

Observe your baby

Don't hesitate to select a product with a slightly higher or lower TOG if you know your baby is particularly cold or warm. His body temperature is the best barometer for your final choice. The most important thing is to make sure your baby never overheats


  1. Why choose Perlimpinpin sleep sack?

All Perlimpinpin sleep bags are tested by independent laboratories and testing facilities for quality components and safety attributes that complies to international, American and UK requirements.

  1. What to choose if baby isn’t born yet?

The best option is our newborn sleep sack as it offers the ideal temperature for newborns as well as a unique and practical design with its reverse zipper for frequent diaper changes and swaddle option (arms in).

  1. What to wear under baby's sleep bag?

There are many options available to you. Some babies will like to be dressed only in a onesie while others (depending on the season) will like to wear pajamas under. Make sure to adapt baby’s clothes according to the season and baby's comfort. Consult our guide below to determine the best combination of clothing for baby.

  1. Why doesn't the Perlimpinpin sleep bag have snaps on the shoulders?

Very popular question! Our simple and secure reverse zipper design avoids the addition of small parts that could break off and cause a choking hazard. Little tip! Start putting on the sleep bag on the shoulder opposite to the zipper to make it easier to put on.

  1. Why use a sleep sack instead of a blanket?

Because it's so much easier! But more importantly, to meet the new Health Canada safety recommendations; blankets should not be used when baby starts to move. Therefore, the sleep sack (also called wearable blanket) becomes the clever answer to safe sleep while providing a sense of comfort to baby.

  1. My baby sweats easily, which material should I choose?

Bamboo fiber is known for its outstanding breathability. It evaporates excess moisture while maintaining the comfort of a tempered body heat.


What to wear under a sleep bag