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Metric Culprits

The Great Metric Rip-Off

There is incontestable evidence that metric conversion is the primary cause of "downsizing", whereby packaged foods and goods are reduced on conversion from pounds and pints to grams and millilitres. The typical sequence of events is that companies first delete lb/oz/pint indications from product packaging and replace them with metric equivalents. At some point after references to traditional units have been removed, the physical quantity is decreased.
Metric reduction goes beyond the trimming off of one or two grams to prevent odd numbers (eg 454g to 450g). Research shows that metric conversion is accompanied by reductions of up to 10% or 15% with no comparable decreases in price.

Metric Milk

The conversion of milk containers from pints to metric has led to routine reductions of around one-eighth in quantity. Reductions of milk are rarely matched by proportional price decreases:

Express Dairies   We have provided Express Dairies with a separate webpage; please click here.
Co-op   Whereas the Co-op's four-pint containers were priced 83p (September 2000), their two-litre containers cost 79p. While the two-litre price tag is 4p less, the price in real terms of the Co-op's metric milk is 8% higher.
Spar and Londis   In 1995, readers' letters to newspapers reported that Spar and Londis replaced their 4-pints with 2-litres (3½ pints) with no change the price.
Dairy Crest
The two bottles to the right, produced by Dairy Crest, appear the same but, whereas the one to the left contains two pints, the other contains a litre, the equivalent of only 1¾ pints.
Two bottles of milk

This is a Watson's Dairy label for 1 pint cartons... Watsons 1 pint

...and this is for 500ml. Note how there is no pint equivalent. Watsons 500ml
St Ivel On conversion to metric, 12oz tins of powdered milk were reduced in price by 10 pence (2%). However, the quantity of powdered milk in each tin was reduced by 12% to 300g (10½oz), meaning a real price rise of 10%.

Some companies mix metric and imperial containers by introducing one-litre bottles alongside single pint cartons. This can be misleading since a customer, relying on the 'price per pint', may pick up a litre assuming it to be two pints rather than 1¾ pints. To test this point, BWMA researchers asked a number of shop assistants for "two pints of milk"; in each case, the assistant responded by passing over a one-litre container.

Canned Foods

One of the purported benefits of the metric system is that it standardises can weights. However, even tins of identical physical size vary in weight due to differing product densities. Densities will be low if the product contains oil and high if the product contains dissolved solids, such as sugar. Moreover, within the volume of the can, a certain percentage gap, known as the headspace, is required to maximise the safety of the can. This headspace varies according to the filling method or sterilisation process used. Thus, conversion to metric for canned foods does not lead to "rationalisation" of can sizes; in fact, the evidence shows it leads to weight reductions as producers take advantage of the switch. For instance:
Simpson Ready Foods  In 1990, Simpson reduced its range of 15oz meat cans (Ready Dinner, Beef Casserole, Irish Stew and Chicken Casserole) to 400g (14.1oz). No prices were reduced. In 1995, Simpson conducted a similar exercise for its vegetable meals (Mild Curry, Hot Curry, Lentil Dahl, Chilli). Weights fell from 425g (formerly 15oz) to 400g while prices remained unchanged.  
Campbell's In 1988, labels on cans of stew (Irish, Beef, Chicken) and Ready Meals (Chilli Con Carni, Beef Curry, Chicken Curry) were changed from 15oz to 425g. During 1990-1992, all cans were reduced to 392g (13.8oz).
Wilsons of Scotland Reduced seventeen varieties of canned steak, stew, mince and curry, by over an ounce, on conversion from 15oz (425g) to 392g.
Casserole Canned meats were decreased from 15oz to 405g with no change in price. Half size 7½oz cans were relabelled as 212g and then reduced to 205g.
Heinz Between 1993 and 1995, eight varieties of Baked Beans (Curried, Burger Bites, Italian, Hot Dogs, Mini Sausages, Pork Sausages and Weight Watchers) were reduced from 225g (previously 8oz/227g) to 205g.
Grants Scottish Foods In 1992, reduced their range of Highland Casseroles (Lamb, Beef, Chicken, etc) from 425g (15oz) to 400g and later to 392g.
Campbell's Four varieties of Meatballs were trimmed by half an ounce in 1988 when 15oz cans were replaced with 410g cans. Prices remained the same.
Heinz   425g cans (15oz) of Spaghetti reduced to 400g (14.1oz) in 1995.
Crosse & Blackwell Spaghetti in Tomato Sauce fell by half an ounce from 15oz to 410g in 1994, as did its Alphabet Spaghetti and two varieties of Healthy Balance Spaghetti.
HP Varieties of children's Spaghetti Shapes, such as Postman Pat and Batman, sold in 15oz cans, were relabelled 425g in 1990 and reduced to 410g in 1995.
Crosse & Blackwell Crosse & Blackwell's Pasta & Sausages and Pasta Bolognaise cans fell from 15oz to 405g (14.3oz). Prices remained the same.

Spices, Sauces and Spreads

Schwartz herbs and spices. Spot the difference.

Imperial and metric jars, side by side, the metric jar (to the right) containing 8% less than the imperial.

Below: creeping metric reduction. Labels change from 1oz/28g to 28g and then to 26g.
Shrinking Schwartz
Shrinking Schwartz

Hellman's Real Mayonnaise, CPC (UK) Jars of 8oz, 16oz and 24oz reduced to 200g, 400g and 600g respectively (equivalents to only 7oz, 14oz and 21oz).

Hazlewood Foods Knocked an ounce off its Tomato Ketchup on conversion from 22oz to 600g in 1990.

Harmony Converted Shoyu Soy Sauce from 10 fl oz to 250ml (minus 12%) with no price reduction.

Colmans In 1990, Colmans English Mustard was reduced from 2oz (57g) to 50g.
Crosse & Blackwell On converting Waistline Tartare Sauce from 9oz to 210g, Crosse & Blackwell cut prices by 5%. However, 210g is the equivalent of only 7.4oz, so real prices rose by 13%.
 Quaker Oats Reduced seven varieties of Sutherland Spread from 2oz to 53g (minus 6%) while raising the price.
 Napolina Trimmed half an ounce off its range of Mushroom, Bolognaise and Neapolitan Sauces when it converted from 15oz to 411g.

Sliced Meat, Sausages

Bowers "454g/1lb" Bowers 400g packaging
Bowers Prepacked sausages are sold traditionally in 1lb packs. On the left is packaging for a 1lb pack of Bowyers pork sausages, marked "454g 1lb". But watch out for Bowyers Irish sausages (right). Bowyers Irish sausages are sold in metric packs; the packaging omits any reference to lb/oz and the quantity is only 400g (14.1 oz).
Mattessons In 1993, Mattessons reduced sixteen varieties of sliced meat from 4oz (labelled 113g) to 100g. In no instance did Mattessons make a comparable price reduction. For example, a 4oz packet of Sliced Ham was reduced by half an ounce but stayed at its price of 99 pence, meaning a price rise in real terms of 12%.

The prices of some items appeared to reduce during metric conversion, for instance, German Style Sausage from 85p to 82p; however, in real terms, this represented a price rise of 8%. The prices of some packs such as Chopped Pork and Ham rose in real terms by a whopping 17%, but the bulk of this increase (10%) was masked by metric conversion; only the 7% portion of the price increase was visible. The full list of Mattessons concealed price rises is provided in this table:
 Mattessons Price when sold in 4oz packs Visible price change when sold in metric 100g packs Price change in real terms
Sliced Ham 99p 99p +12%
Smoked Ham 99p 99p +12%
Honey Glaze Ham 99p 99p +12%
Turkey and Ham Loaf 59p 63p +17%
Chopped Pork and Ham 63p 67p +17%
Ham Cured Shoulder 85p 89p +16%
Tandoori Spiced Chicken 89p 93p +15%
Smoked Turkey Breast £1.09 £1.12 +14%
Pork Luncheon Meat 57p 59p +14%
Honeyroast Ham £1.09 £1.12 +14%
Maryland Ham 93p 97p +13%
Thin Sliced Ham £1.05 £1.08 +9%
German Style Sausage 85p 82p +8%
Liver Sausage 57p 59p +6%
Garlic Sausage 89p 82p +4%
Danish Salami 89p 82p +4%
Asda In 2000, Asda sold "35% less fat" pork sausages. Packs were of comparable physical size to other packs of sausages, containing eight sausages and costing £1.49. However, whereas a pack of standard sausages weighed 454g (1 lb or 16oz), the less fat sausages were sold in metric packs of 400g, the equivalent of only 14.1oz. Less fat should not mean less sausage!


12 oz and 330ml Pepsi An international comparison rather than a case of downsizing. The Pepsi can to the left is a standard American size containing 12 US fl oz or 355ml and sold in the USA, Canada and SE Asia. The Pepsi can to the right is a metric size and contains 330ml, the equivalent of 11.2 US fl oz.

Barr Soft Drinks Reduced their 38 fl oz bottles by 3 fl oz when converting to one-litre bottles. There was no reduction in price.

Canada Dry Cola Appeared to reduce their prices by 16% when introducing 250ml cans. However, since the 250ml cans represented a 23% reduction on the former fluid ounce cans, real prices rose by 7%.

Corona Soft Drinks Replaced their 12 fl oz C-Vit Blackcurrent Health Drinks with 33cl rather than the equivalent of 34cl, and their 18 fl oz cans with 50cl rather than 51cl.
Beecham Foods In 1985, Beechams reduced the quantity of Horlicks powdered malt drink without a reduction in price:

1984 1985 Metric quantity
in lb equivalents
½lb 200g 0.44 lb
1 lb 400g 0.88 lb
3 lb 600g 2.6 lb
5 lb 2kg 4.4 lb
10 lb 4kg 8.8 lb

Since metric conversion, Horlicks has periodically sold promotional jars offering customers "10% extra free - 440g for the price of 400g". However, since Horlicks powdered malt drink used to be sold in jars of 1 lb (454g), the offer of 10% free is in fact 2% less than what used to constitute a standard jar.

Sweets and Snacks

Imperial bag   Metric bag
Pollard wrapper 8oz   Pollards 200g
    Metric bag (reverse)
Pollards sweets

To the above left is an imperial bag of Pollard sweets. The "Full ½lb" weight is clearly displayed near the top. The strip bar across the bottom states, "Net Wt 8oz 227g". To the above right is a metric Pollards bag. Note how the metric bag makes no reference to weight on the front; the ½lb flash is absent and the strip bar is empty. Only on the reverse of the metric bag is the weight to be found - 200g (in very small print, just under the Best Before date; see right). Both these bags were sold at the same price.
  Rear of 200g wrapper

2oz ("56g") and 50g, side by side    
  Photo of metric and imperial Pringles   Until 1999, Pringles were sold in 2oz tubes, marked "56g". In 2000, these cartons were replaced with tubes containing 50g. Prices were not reduced.

Fox's Glacier Mints has its own page: please click here

 Terry's York Boxes of Spartan chocolates were converted from 1lb to 400g, and ½lb to 200g. Prices declined by 3½% (from £2.79 to £2.69 and £1.40 to £1.35). However, since the weight reductions represented a decrease of 12%, real prices increased by 8%. Terry's York did the same with their Carousel boxes of chocolates.
Romix Foods Reduced their Dry Roast Peanuts from 4oz to 100g (minus ½oz) while raising prices a penny a bag.

Thorntons 57g (2oz) bags of chocolage buttons costing 59p were replaced with 40g bags costing 45p - a real price increase of 8%.
Lyons Tetley  Reduced milk and plain chocolate Polka Dots from 4oz to 100g with no price decrease.
Cadbury's Roses and Spice chocolates were sold in boxes of identical height, but only the former contained ½lb; Spice chocolates contained 205g, 10% less, even though sold at the same price.
Imperial Murrays Metric Murrays
In 1999, bags of Trebor Bassett Murray Mints carried the message, "Changing soon to Bassett's Fundays - Your trusted favourite sweets in new packaging". A few weeks later, new packaging was introduced - but whereas the former bags weighed 227g, the new packaging carried 200g (ie a reduction from 8oz to 7oz). Prices remained the same. Trebor Bassett carried out the same reduction for Mint Imperials, Everton Mints and Black Jacks and Fruit Salads. Murray Mints 227g Murray Mints 200g (reverse)

Foods sold Loose

Cheating on weight conversions does not just apply to packaged foods and drinks; it applies also to foods sold loose. On January 1st 2000, some of the traders who adopted metric unit pricing used the switchover to increase prices. For example:
  • The Costa Coffee shop in Hammersmith re-priced its Colombian filter coffee from £5.35/lb to £1.50/100g, a large fall in the unit price - until one realises that the equivalent of £1.50/100g is £6.80/lb, a rise of 27%.
  • Another coffee shop, when requested to serve out half a pound, served 220g instead of the equivalent of 227g, yet charged the full £2.48 price of a half-pound. When the customer queried this, the assistant explained she was working from a conversion chart issued by the wholesaler.
  • Numerous confectioners were observed on "M-Day" to convert prices per quarter-pound to 100g without proportional price decreases.
  • Woolworths sneaked in a price increase on its loose "pick 'n mix" sweets when changing the price from 65p/qtr to 59p/100g, rather than the actual equivalent of 57p/100g.
  • Grocelle Ltd, a company that sells snacks through shops such as Bottoms Up off-licences, increased prices overnight by placing adhesive "per 100g" labels over the former "per qtr" markings. Here is one such example:
Unit price label
Seen close up, the "Per Qtr" is still just visible under the 100g sticker:
Weight decrease close up

Grocelle made prices increases by changing their entire range in this way, as illustrated in this table:

Product Price per Qtr, changed to 100g "Concealed" price increase (per Qtr)
Honey Roasted Cashews £1.99 28p
Pistachios £1.48 19p
Rice Crackers £1.35 18p
Yoghurt Raisins £1.30 17p
Salted Mixed Nuts & Raisins £1.05 14p
Bombay Mix 99p 13p

Sainsburys; another unit pricing scam

Sainsbury's has employed a scam that, while not constituting reduced measure, plays tricks on consumers' perception. This is by switching the format in which metric and imperial unit prices appear. When showing the price per lb, Sainsbury's displayed the imperial as large as the metric, because the price per pound appears less than the price per kilogram. For instance:

88p per kg
40p per lb

However, when display prices per 100g and per qtr, Sainsburys displayed prices as:

30p per 100g
34p per qtr

Sainsburys switching of emphasis on typeface sizes was guided not by preference for any particular system but by whichever unit appeared to offer shoppers the lower price.

Sainsburys only stopped this practice in August 2000 after competitor Tesco announced its re-adoption of lb/oz. Sainsbury's responded by increasing the size of price per qtr indications to almost the same size as the metric and placing boxes around them for emphasis. This experience neatly illustrates how competition from stores that use lb/oz propels stores that use metric to improve and clarify product information.

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