Low-cost inkjet printers could cost users more than 50 times their price over the course of 18 months, according to research by vnunet.com's sister title Computeractive.

Many consumers are tempted by cheap inkjet printers now that costs for some have fallen to as low as £30.

But tests conducted by Computeractive experts found that what might seem a great deal at first can backfire when it is time to replenish the ink supplies.

Computeractive editor Dylan Armbrust said: "An exceptionally attractive purchase price may obscure the ugly truth about the actual expenditure you can expect to make during a printer's lifespan.

"Replacement cartridges may cost as much or more than the cost of the printer and, in some cases, it would be cheaper to buy a new printer."

To calculate the real cost, buyers need to consider several factors, not least the cost of the ink.

Obviously the quantity of ink used will vary from user to user, but even the most casual user will need to replenish ink supplies a couple of times a year.

The situation is further complicated by the fact that not all ink cartridges are equal; one manufacturer's cartridges may be cheaper, but a rival's may last longer.

"This information is almost impossible to discern at the point of purchase as the only information that tends to be writ large on sales materials is the price," warned Armbrust.

A report by the Office of Fair Trading in December 2002 stated that it would take action against manufacturers and retailers which failed to give consumers clearer information on pricing in the inkjet printer market.

"This survey was dated December 2002. Well over a year later our results suggest that consumers are still at serious risk of being ripped off," said Armbrust.