If you're addicted to caffeine, Toronto's coffee kings aren't about to go easy on you.

McDonald's has declared a java war on Tim Hortons. For the next two weeks, the fast-food giant will offer their customers a free small cup of coffee with no purchase required.

They made the announcement on the first day of Tim's "Roll up the rim to win" campaign, a wildly successful contest that gives coffee drinkers the chance to win cars, laptops, money, free java and donuts.

About seven of every 10 coffees sold are bought at a Tim Hortons outlet, according to chain spokesperson David Morelli. A recent study concluded that 67 per cent of Canadians drink at least one cup of coffee a day.

Deborah Feaver, a McDonald's owner, said she thinks giving Tim's some competition is a good idea.

"We have great coffee and we just want to create awareness among customers that there is an alternative out there that serves excellent coffee," she said.

This isn't the first time McDonald's has tried to go head to head in a java war.

Last year, the chain launched a similar campaign, offering customers free coffee for a limited time in April. That along with other java-geared promotional campaigns have helped increase coffee sales at McDonald's by 30 per cent.

This year, Country Style is also getting stirring up some competition, offering their customers a free medium coffee on Wednesday mornings.

Morelli says Tim Hortons welcomes the competition.

"Both times that one of our main competitors gave away their products for free, the number of customers who came to our stores actually increased during those two weeks," he told CTV Toronto.