No doubt you've noticed that laundry detergents have been getting more and more concentrated. That saves manufacturers money on shipping costs because of less packaging. But Consumer Reports says people are plenty confused about how much detergent to use.

It turns out many people use twice as much detergent as they need, according to an industry trade group. That can make the rinse cycle longer. It also wastes money. And if you think you could do twice as many loads with a 2X concentrated detergent, think again.

It turns out that there’s no standard definition for what those concentrations mean. It’s only twice as concentrated when you compare within the same brand.

For example, an Era detergent says it's 2X concentrated and it can clean 32 loads. It's the same size as a Tide detergent, which says it can do 30 loads. But the Tide’s not concentrated.

Figuring out how much detergent to use isn’t easy either. An All detergent says to fill to line three for large loads and to line two for normal loads. But those lines are virtually impossible to see.

So you may need to get a bit creative. Take Consumer Reports’ top-rated detergent for top-loaders—Wisk Deep Clean. The fill lines are really tough to see. So use a permanent marker and make a nice bold line. That way you won't end up wasting detergent.

If you have a front-loader, Consumer Reports named Target's Up and Up HE Fresh Breeze a Best Buy. It costs 11 cents a load, but only if you use the right amount.