There are many different types of laundry detergents.
There powder and liquid forms. Both work well.

All top brand detergents are strong and can be
cut to save you money.

The companies want you to use alot so that you will buy more sooner.

To save money:

With powder use half of what the instructions call for, and it will go further and your clothes will get just as clean.

With liquid save a bottle and pour half into it and mix with water. Now you will have two bottles.

Keep in mind when looking for bubbles, all detergents add a sudsing agent in order to please our idea that bubbles mean that your laundry is getting cleaner. So if you do not see alot of suds it's ok, you still have the cleaning agent working hard.

Cutting detergent can help alleviate skin allergies.

To save even more money, you can do the same with fabric softener.

Liquid, save a bottle, mix with water
Sheets, cut your sheets in half or only use one per load.

All fabric softeners have a fire retardant warning on them. Please read it carefully.