Timing can be everything when it comes to sales.
"We analyzed all the items that go on sale for hundreds of different retailers and, as we did that, we started to find trends as to which type of items did better on which days of the week," said Charlie Graham, Shop It To Me chief executive.
For 30 straight days, Shop It To Me analyzed more than 343,000 newly marked down women's items.
The site found on skirts on average were 77 percent off on Sundays versus 52 percent on other days. Jeans on Sundays averaged 50 percent as opposed to 42 percent off on other days.
Mondays was the best day to look for dresses -- at 54 percent off versus 45 percent on other days. Mondays were also hot for jewelry -- an average of 47 percent off compared to 40 percent.
On Thursdays, shoe sales were 39 percent off versus 37 percent off on other days.
On Fridays, sunglasses were 44 percent off compared to 39 percent on other days.
Search engine Extrabux found Sundays are the best days to buy appliances. The website also found that books on average are 11 percent percent cheaper on Saturdays, and cameras are 4 percent less expensive on Mondays.
And sales on airline tickets typically peak at about 3 p.m. on Tuesdays, according to Farecompare.com.
Shop It To Me sends shoppers emails when their favorite items by specific designers go on sale.
Shoppers input their dress size, the designers they want, the maximum they're willing spend and the percentage off they're looking for.
"I definitely really love fashion and love finding good deals," site user Justine Kallaugher said. "It's a thrill when you find something on sale and a deep discount."
Justine Kallaugher said she found a Nicole Miller dress regularly priced at $400 for $112.
Quia Querisma, another Shop It To Me regular visitor, said she has found big discounts on all sorts of ladies clothes and accessories. She bought her favorite Hunter rain boots for $140, cheaper than the regular price of $175.