TOG Chart for Babies: Sleep Sack TOG Rating Guide

If you've been shopping for a sleep sack, swaddle, or footed sleep bag, you've probably come across the term "TOG" and wondered what it actually means. For newborns, the right TOG depends on the season and room temperature, with 20 - 22°C (68–72°F) generally considered a comfortable range for the nursery. As a guide, use 0.25 - 0.6 TOG for warmer rooms in the  summer, 1.0 TOG for spring and mild fall rooms (20 - 24°C / 69 - 74°F), 2.5 TOG for cooler rooms (16 - 20°C / 61 - 68°F), and 3.5 TOG when extra warmth in winter. Check the back of your baby's neck or chest—not hands or feet—to make sure they’re comfortably warm.

This guide covers everything new parents need to know  about TOG including what it means, why it matters for your baby’s comfort and safety, how to choose the right TOG for different room temperatures and season, and how to tell if your little one is comfortably dressed for sleep.We’ve created the ultimate TOG guide for newborns to help make choosing the right TOG a little easier. After reading this guide, you’ll learn: 

• What is a TOG rating? 
• Why does TOG matter?
• How do I know I have the right TOG?
• What TOG does my newborn need for the fall, winter, spring, and summer? 

Let’s get started.

TOG stands for Thermal Overall Grade and is a rating used to measure how warm a sleep bag or wearable blanket is. It can help you choose the right sleep bag for your baby based on the temperature of your baby’s sleep space..

The TOG rating system works on a simple scale: the higher the TOG, the warmer the sleep bag or footed sleep bag is. If the TOG rating is low, the wearable blanket is lighter and is better for warmer room temperatures, especially during spring or summer. 

Want to learn more about TOG ratings? Read our complete guide to TOG ratings.

TOG stands for Thermal Overall Grade: a unit of measurement that tells you how thick or warm a wearable blanket is. The system works on a simple scale: the higher the TOG rating, the warmer the sleep bag or footed sleep bag, and the better suited it is for cooler temperatures. Lower TOG ratings are lighter and better suited for warmer temperatures like during spring or summer.

Babies aren’t able to regulate their body’s temperature as well as adults. Knowing the right TOG to buy can help keep your baby safe and comfortable while they sleep. While it can be tempting to layer your baby when the weather cools down, this can lead to overheating, a risk factor for Sudden Infant Death Syndrome (or SIDS). This is also why sleep experts recommend a wearable blanket over loose blankets in the crib. A properly fitted, TOG-rated sleep bag keeps your little one warm without need for loose bedding.

Choosing the right TOG also depends on other factors including: 

• Your child’s room temperature: The temperature varies season by season and depends on the temperature you set your heating at and if you are running an air conditioner in the room. To figure out your child’s room temperature, we recommend getting a thermometer and measuring how hot or cold the room is. An ideal room temperature is between 20° - 22°C (68° - 72°F). 
• The clothing they wear during sleep: ​​Any extra layers like PJs or onesies count as an extra layer of insulation. You’ll want to ensure that the layers work with the TOG rating and check on your child to make sure they’re not too cold or overheating. 
• Your child’s overall temperature: Little ones all run at different temperatures just like us adults. You can touch the nape of their neck to check if they’re too hot or cold. Keep in mind that extremities like their hands and feet will not tell you how cold or hot your little one actually is. 
• The materials the wearable blanket is made from: Fabrics are not equal and do not provide the same amount of warmth. Some materials are more breathable than others and some materials provide more insulation than others.

For room temperatures around 20 - 24°C (69 - 75°F), a short-sleeve onesie can be worn under a 1.0 TOG sleep bag. This makes 1.0 TOG a versatile option for mild temperatures like during spring and fall. There’s no need to add a loose blanket since the sleep sack is enough to keep your little one comfortably warm.

For cooler room temperatures around 16–20°C (61 - 68°F), pair a 2.5 TOG sleep bag with a long-sleeve onesie or lightweight pajamas. If your baby’s room is warmer, use a lighter layer, a short-sleeve onesie, or lower TOG sleep bag. If you’re unsure whether they’re comfortable, check the back of their neck or chest.

A 3.5 TOG sleep bag is designed for colder room temperatures around 10 - 16°C (50–61°F). In warmer rooms, choose a lower TOG to help prevent overheating. Always choose your baby’s TOG based on their actual room temperature rather than the season.

For  fall, a 1.0 TOG or 2.5 TOG sleep bag or footed sleep bag may be a good choice for your baby depending on the temperature of their room. A  1.0 TOG is designed for  mild room temperatures around 20° - 24°C (69° - 74°F), while 2.5 TOG is better suited for rooms around 16° - 20°C (61° -  68°F). 

Nest Designs sleep bags are available in soft, breathable fabrics like GOTS-certified organic cotton and bamboo, with warmer styles featuring Sorona®️for added warmth. Thoughtful details like removable sleeves, foldover mittens,and foldover footed cuffs on select sleep bags help keep your little one comfortably warm and cozy while they sleep. 

If you’re using our Swaddle Sleep Bag or Startle Stop Sleep Bag, remember that the swaddle wings add warmth - about 0.5 TOG more. Be sure to consider the combined TOG when choosing the right option for your baby’s room temperature.

For colder winter nights, a 3.5 TOG or 4.0 TOG sleep bag may be a good choice if your baby’s room temperature is around 13-16°C (31°F). Nest Designs’ 3.5 TOG sleep bags are made from GOTS-certified organic cotton and filled with Sorona®️for added warmth. We choose organic cotton for its soft, breathable feel against delicate skin. Because it’s grown without synthetic pesticides or fertilizers, it is a more thoughtful choice for your little one and the planet. Paired with lightweight Sorona, it helps keep your little one cozy on colder nights.

The spring’s warmer weather means you can shed the heavier layers and dress your newborn in a lighter TOG. Depending on your baby’s room temperature, we recommend opting for a mid-light weight TOG like 1.0. These are great for rooms 20° - 24°C (69° - 74°F). 

Nest Designs 1.0 TOG sleep bags and footed sleep bags are made from a range of materials. These include GOTS certified organic cotton, rayon from bamboo, and our signature avocado bamboo. These wearable blankets are made with thoughtful features like removable sleeves, foldover handcuffs, and foldover foot cuffs.

Bamboo is especially loved for its buttery-soft, breathable feel against delicate skin. It’s naturally hypoallergenic, moisture-wicking, and temperature-regulating which helps keep your little one comfortable throughout the night, especially for little ones with sensitive skin like eczema. 

Who doesn’t love the feeling of warm summer skin? But for newborns who can’t regulate their body temperatures as well as adults, the warmer weather can quickly become uncomfortable. For the summer nights, Nest Designs’ baby sleep bags and footed sleep bags come in 0.25 TOG, 0.5 TOG, and 0.6 TOG. These are lightweight to ultra-lightweight TOGs that are made for hot to extremely hot weather. As a guide, 0.23 TOG is designed for rooms around 26–29°C (79–84°F), 0.5 TOG for 25-27°C (77-81°F), and 0.6 TOG for 24-26°C (75-79°F).

Our lightweight sleep bags and footed sleep bags are made from soft, breathable, and hypoallergenic fabrics including bamboo, bamboo silk, bamboo Pima, and bamboo jersey. They are moisture-wicking and temperature-regulating, helping keep your baby cool and comfortable on warmer nights. Depending on the style, you’ll also find sleeveless, ¾ inch sleeve, and removable long sleeve options for added versatility.

The right TOG should help your baby stay comfortably warm without overheating. Since every baby is different, use their room temperature as a starting point, then check how they feel while they sleep. The back of their neck or chest should feel comfortably warm and not hot, sweaty, or clammy.

Your baby is too hot if they’re showing these signs:

• Skin feels hot or unusually warm to touch
• Flushed skin or red cheeks 
• A sweaty neck
• Damp or sweaty hair
  

Remember, check the back of your baby’s neck or chest rather than their hands or feet, which can naturally feel cooler. If they’re feeling hot or sweaty, remove a layer and check their sleepwear and TOG based on the room temperature.

Rapid breathing, unusual lethargy, floppiness, or difficulty waking your baby can be signs that something more serious is wrong and should be treated as a reason to seek medical attention.

To feel if your baby is too cold, feel the back of their neck or chest. If their skin feels cool or cold, they may need another layer or a warmer TOG. 

Keep in mind that little hands, feet, and noses often feel cooler, even when your baby is perfectly comfortable. If your little one seems unusually fussy or has trouble settling, temperature may be one of many reasons. 

The best way to check: touch the nape of the neck, not their hands, feet, or nose

As a rule of thumb, you can dress your baby in one extra layer than what you’re wearing in the same environment 

TOG doesn’t change based on your baby’s age. The right TOG is still determined by the temperature of their sleep space, while the size of their sleep bag will change as they grow. Always check the product’s size guide to find the right fit for your little one. 

As your baby grows, their sleep bag will change too. Once your baby shows signs of rolling, usually around 3-4 months, it’s time to transition out of swaddling to an arm-free sleep bag. 

As your baby grows, their ability to regulate body temperature develops, but TOG should still be chosen based on the temperature of their sleep space.

Choose your baby’s TOG based on their room's actual temperature at the time, not the clock. If the nursery runs warmer during a sunny afternoon nap than overnight, you may find a lighter TOG is more comfortable for naps and a warmer TOG works better at night.

At Nest Designs, we choose soft, breathable materials with your little one’s comfort in mind. Depending on the style and TOG, our sleep bags and footed sleep bags are made from materials including: 

• GOTS-certified organic cotton: Made without toxic chemicals, dyes, or GMOs, GOTS-certified organic cotton is soft, breathable, and gentle on  delicate newborn skin.
• Bamboo (including bamboo silk, bamboo Pima, bamboo jersey, and signature avocado bamboo): Bamboo is loved for its buttery-soft, breathable feel and moisture-wicking, temperature-regulating properties that help keep little ones comfortable throughout the year, especially for babies with sensitive skin or eczema.
• Sorona®: An eco-friendly, fully biodegradable fill, it is used in our 2.5 and 3.5 TOG sleep bags and footed sleep bags to provide lightweight warmth with a soft, plush feel that helps keep little ones cozy on cooler nights.

Many of our sleep bags also feature removable sleeves, foldover mitts, and foldover foot cuffs, giving you the flexibility to adjust their coverage and keep your little one comfortable as temperatures change, without always needing to switch sleep bags.Our lightest summer sacks (0.23–0.6 TOG) come in sleeveless, ¾-sleeve, and removable long-sleeve styles for hot to extremely hot rooms.

Newborns and infants can't regulate their temperature as well as adults can. Overdressing is a known risk factor for Sudden Infant Death Syndrome (SIDS), which is why sleep experts recommend a wearable blanket over loose blankets in the crib. A properly TOG-rated sack keeps the baby warm without the suffocation risk loose bedding carries. Read the AAP's full safe sleep recommendations.

Beyond room temperature, a few other factors shape the right TOG for your baby:

• Your child's room temperature. This varies by season and by your heating/AC settings. An actual thermometer beats guessing. Ideal nursery temperature is generally 20–22°C (68–72°F).
• The clothing worn underneath. PJs or onesies count as extra insulation, so make sure layers work with the TOG rating rather than against it.
• Your child's overall temperature. Every baby runs a little differently, just like adults. Check the nape of the neck, and never rely on hands or feet, to get an accurate sense of their temperature.
• The materials of the wearable blanket.Fabrics aren't interchangeable; some breathe better, some insulate more, even at the same TOG number. Different fabrics offer different benefits when it comes to breathability, moisture-wicking, and overall feel. Consider both the TOG and fabric when choosing a sleep bag.

The right TOG comes down to three things: their room temperature, what your baby's wearing underneath, and the sleep bag itself. A properly chosen sleep bag or footed sleep bag helps your little one sleep more comfortably—and hopefully longer, too. Still not sure which TOG is right for your nursery? Contact us and we'll help you find the right fit, or explore our full range of sleep bags and footed sleep bags by TOG rating.