What is the difference between Dyson DC33 and DC14? Read comparison here.
In this post, DC33 refers to DC33 Multi Floor, DC14 refers to DC14 Multi Floor.
Dyson DC33 VS DC14 Compare
images from manufacturer

Suction Power
DC14 has a suction power of 250 air watts while DC33 has 240 air watts.

Hose
The DC14 has a metal hose while the hose of DC33 is plastic.

Tools
DC14 comes with a brush tool, stair tool, and crevice tool; whereas DC33 comes with a stair tool and combination accessory tool.

Bin Capacity
DC14 has a bigger bin.
The bin capacity of DC14 is 0.71 gallons while DC33 has a 0.61 gallon bin.

Weight
DC33 is lighter.
DC14 weighs 18.56 lbs while DC33 weighs 17.6 lbs.

Cord Length
DC14 has a 35.4 ft cord whereas DC33 has a cord length of 35 feet.

They same things these two Dyson vacuum cleaners have:
fixed wheel, Root Cyclone technology, 12 amp motor, telescope reach wand, lifetime washable HEPA filters, five years warranty.