Tog Rating: How to Choose the Best Tog for Your Duvet

At Downduvet.co.uk all our duvets have a verified tog rating which tells you how warm they are. Tog, which stands for thermal overall grade, is a measurement of the heat retention capacity of a fabric. In this case, the down or feathers within a duvet. The higher the tog rating, the toastier you will be at night.

No one wants to sweat or shiver through the night, so getting a duvet with just the right amount of warmth is essential. Luckily, the tog rating system is scientific and precise, making it easy to choose the right duvet.

The insulating power of a duvet is determined by factors including the quality and weight of the down, and the way it was manufactured. Using tog rating, we can breakdown duvets into seasonal styles based on the amount of warmth which they provide. Keep reading to learn how this translates to shopping for a duvet and the science behind tog testing.

Thermal classes

4.5 Tog: The Summer Duvet

Our Summer duvets are light and airy, almost unbelievably so. Box stitching and high quality down ensures these duvets will keep you cool while providing a comfortable covering throughout the summer. With a tog rating of 4.5, they are suitable for most bedrooms.

The duvets manufactured by Dickenbergh, Falkenreck, Dickenbergh Manufaktur and Kauffmann 1st Class are particularly light and cool. Those from Kauffmann, Otto Keller and Bielefelder Verse are a slightly warmer.

6.0 Tog: The SummerPlus Duvet

SummerPlus duvets are also box stitched and light, though less so than summer duvets. This means they are suitable for a greater part of the year, possibly from spring through to mid-autumn, depending on the local climate. If your home is well-heated, a SummerPlus duvet can be used year-round.

The SummerPlus duvets from Otto Keller and Dickenbergh tend to be a little bit cooler. Those from Kauffmann and Falkenreck and are warmer.

9.0 Tog: The Spring/Autumn Duvet

For many people, a Spring/Autumn duvet is ideal because it can be used comfortably almost the entire year in most homes. Spring/Autumn duvets have a tog rating of 9.0. They can be box stitched or of baffle box construction. These duvets will keep you comfortably warm during the cooler nights but are light enough not to necessitate a change every time there is a hot spell.

The coolest Spring/Autumn duvets are those from Otto Keller, Bielefelder Verse and Kauffmann 1st Class. Dickenbergh, Falkenreck and Dickenbergh Manufaktur duvets are a bit warmer. The warmest Sring/Autumn duvets are made by Kauffmann.

12.0 Tog: The Winter Duvet

Rapturously warm, decadently thick and luxuriously soft, winter duvets are perfect for those who need to wrap themselves up, whether for comfort or to fight off chills. With a tog rating of 12.0, winter duvets will keep you warm and cozy in all but the most frigid climates. They are constructed using the baffle box technique to provide the absolute most optimal insulation.

As with other duvet classes, the winter duvets from Dickenbergh and Kauffmann 1st Class are slightly less warm. The warmest winter duvets are made by Kauffmann, Otto Keller, Falkenreck, Bielefelder Verse and Dickenbergh Manufaktur.

15.0 Tog: The WinterPlus Duvet

The lightest WinterPlus duvets are those from Dickenberg and Kauffmann 1st Class. Warmer and heavier WinterPlus duvets are made by Kauffmann, Otto Keller, Falkenreck, Bielefelder Verse and Dickenbergh Manufaktur.

The All Seasons Duvet

An exotic species, these are truly duvets for all seasons. Called the duo-duvet in Germany, All Seasons duvets consist of two duvets with different tog ratings that can be used separately or in tandem.

The lighter of the two duvets is perfect for keeping you cool, fresh and dry on hot summer nights. When things start to cool down come autumn, you can switch to the warmer duvet. Once winter arrives, the two are easily combined to create a seamless winter duvet.

Is a Higher Tog Rating Better?

Tog doesn’t measure the quality of a duvet, or how comfortable the fabric will feel against your skin. Nor does it say anything about the weight of the duvet. Tog tells us how efficiently a specific material will trap warmth. This is known as thermal resistance. The higher the tog rating, the warmer the duvet will feel. Even though tog ratings are a good indicator of how warm you’ll be under a duvet, it’s important to understand that tog is measured under laboratory conditions. Making sure the duvet covers your bed sufficiently is also an important consideration when determining how warm a given duvet will be.

Another factor that can affect how warm a duvet actually feels is the overall quality of its fabrication. A poorly constructed duvet made from cheap materials might have a certain tog rating when brand new and measured in a laboratory, but after a few uses this low quality duvet may lose some of it’s insulating capacity.

How Tog Is Measured

Tog is measured by applying heat to one side of a fabric, and measuring the heat flow to the other side. The tog value of a down duvet is equal to ten times the temperature difference between its two faces (in degrees Celsius) when the flow of heat across it is equal to one watt per m².

Testing the tog ratings of duvets requires highly precise measurements to be taken, and typically involves spreading the duvet over a large rectangular hotplate with the temperature set to 32.5 - 33.5°C, and an ambient temperature of 19.5 - 20.5°C, and measuring the temperature of at least five points to acquire an average thermal resistance over the material.


Down Duvet Buyer's Guide

Choose your duvet in 4 simple steps

  1. Duvet size: Which duvet size do I need?
  2. Tog: Choose the right tog
  3. Fill power: What is Fill Power?
  4. Duvet fabric: Good down belongs in a good fabric

Compare all down duvets by duvet price, size, season, brand, fill power, fabric and down.

Do you have any questions? Feel free to ask us!
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