How strict is EasyJet carryon dimension

Well, I've only taken Easy Jet once and there were sizers at the beginning of the jetway and EVERY person had to drop their carry on into the sizer before the gate agents let them go down the jetway.

Yes. The mean what they say.

What fare class did you book? What is the size of your bag? The Standard Allowance is this 45 x 36 x 20 cm. While the other class is this 56 x 45 x 25 cm. It depends on how much you want to pay.

We had a gate agent that walked down the line of people getting ready to board and was pulling people out that had luggage that was too large. I would even think twice about bringing regular sized luggage as carry-on. I've used EasyJet twice and both times by the time it was my turn to board the overhead bins were full. I was lucky and had checked my luggage anyway.