Myths about using metric

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People sometimes fear using metric due to myths that are often nonsensical. Some of the common ones are listed and debunked below.

Minotour

It is awkward to measure for DIY in metric

With a suitable metric-only or dual unit tape or rule with metric on the upper edge there should be no difficulty. Read more

Food will not taste the same in metric

Taste generally depends on the ratios of ingredients and not their units. Read more

Using metric recipes is awkward

Working in round metric quantities is easy as it is decimal. Food is sold in metric and it is easier if recipes are metric too. Read more

British are incapable of thinking in kilograms

Despite the lack of public education many people work happily in kilograms – not least chefs. Read more

You cannot use metric recipes if you have a gas cooker

There is nothing to stop you weighing or measuring in metric if you cook with gas. Read more

You need more accurate scales if you are cooking with metric

Scale accuracy has nothing to do with the units used. Read more

Metric requires packaging in 10s

The number of items in a package has absolutely nothing to do with the system of units used. Read more

Babies are weighed in pounds and measured in inches

Standard UK measurements for babies are metric. Grams are used for weight and centimetres for length or head circumference. Read more

A4 paper is not metric

The A-series of sizes are defined in millimetres. Read more


It is awkward to measure for DIY in metric

Some people have tried to do metric DIY jobs using dual imperial/metric tapes. However since many retractable tape measures have inches on the top side of the tape they are difficult to use for metric measurements.

Metric-only tapes are easy to use. A few manufacturers have dual unit tapes with metric on the top and these are easy to use too.

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Food will not taste the same in metric

Taste depends on the ratios rather than the units of the ingredients. If you make shortbread using

300 g plain flour,
200 g butter
100 g caster sugar;

it will taste the same as one using

9 ounces plain flour,
6 ounces butter
3 ounces of caster sugar

because the ingredients are in the same proportions.

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Using metric recipes is awkward

Since the mid 1980s many publishers of recipes have tried to sit on the fence with regard to measurement units. In many cases recipes have sensible numbers in ounces but awkward ones in grams.

imperial recipe for shortbread

The example above from a well-known website even has different proportions for metric and imperial. It uses Fahrenheit oven settings even though only Celsius ovens have been sold for decades. Many recipes are cluttered because of multiple units.

metric recipe for lavender shortbread

However many modern British foodwriters use sensible metric quantities, like those above, which are easier to use. Using metric makes sense as food is packaged in round metric quantities and nutritional information is also metric.

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British are incapable of thinking in kilograms

It's curious that opponents of metrication wish to patronise the British people by implying that they cannot understand a simple system which the rest of the world uses daily. Any confusion is due solely to the lack of a good transition plan and the absence of an extensive public education programme.

example bags of sugar

However, it beggars belief that people are not familiar with the litre or kilogram. Sugar has been packed in kilograms since the mid 1970s and fruit juice in litres since the early 1980s. Furthermore:

  • In 1971, Britain successfully changed from £/s/d to decimal currency aided by a two-year public information campaign to every home.
  • Britain has educated children since 1974 in the metric system but has given them little opportunity to practise it outside the school gate.
  • Australia, New Zealand and South Africa, all countries with similar cultures to the UK, are able to think in terms of kilograms. Government-funded public education programmes assisted the people in these countries, unlike the UK.

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You cannot use metric recipes if you have a gas cooker

 

This is one of the silliest myths!

With regard to recipes, the only difference between cooking in gas and electric is the oven settings. Electric cookers are set using the temperature in Celsius while gas cookers use ‘mark’ settings.

Any metric recipe can be cooked in a gas oven providing the correct mark is selected.

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You need more accurate scales if you are cooking with metric

Most scales are sold in metric countries. Some variants have been created with dual scales for the UK market but the underlying technology is the same. Analogue scales will work the same way regardless of the units used.

With digital scales it is important to understand that the accuracy of scales is not the same as the precision to which a weight is shown on the display. A set of scales indicating grams does not have to be accurate to one gram – indeed it is more likely to be accurate to 5 grams.

A problem with many mixed imperial/metric recipes is that the metric values are derived from imperial exactly. For example giving ‘227g/8 oz’. You do not have to weigh out exactly 227 grams any more than you weigh out exactly 8 ounces and not a fraction above or below! Weighing using metric-only recipes is easy as the weights are given in round numbers of grams.

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Metric requires packaging in 10s

Just because products are say weighed in grams or in cans measured in millilitres does not dictate how they are to be packaged.

8 pack of cans of lager

It is possible to buy eggs by the half dozen in France, buy a pack with 5 chicken breasts (600 grams), buy an 8-pack of Danish Carlsberg lager (500 ml cans), buy a pack of 12 Cumberland chipolata sausages (425 grams), buy a pack of 6 German Bratwürste or Ferrero Rocher chocolates in a pack of 16 in each case using metric weights and measures.

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Babies are weighed in pounds and measured in inches

Health professionals use metric measurement as a standard. This is internationally accepted practice and is the basis for patient record keeping. Babies are weighed in grams and measured in centimetres.

baby weight chart

The above extract from a Department of Health chart shows the normal weight range for a baby boy.

Unfortunately so may parents have requested the weight of their babies in imperial that professionals routinely provide conversions.

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A4 paper is not metric

This is complete nonsense.

The ISO A series of paper sizes are derived from the base size of A0 having an area of 1 square  metre. All A-sized pages have a ratio of long side to short side equal to the square root of 2, which is approximately 1.414.

This number has been chosen so that when a page is divided in half (cutting through a line parallel to the shorter edge) the two smaller pieces have the same ratio of length to width as the original piece. This results in some odd looking dimensions in millimetres which may account for the misunderstanding.

For example

A5 is 148 × 210 mm. A4 sheets are double the size of A5 so are 297 × 210 mm. A3 sheets are double the size of A4 so are 297 × 420 mm

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